Abstract:
This study investigated the design and feasibility of noise mitigation strategies for installation in modular expansion joints (MEJs), with a focus on Washington state’s SR 520 bridge. The three main sources of noise from MEJs include resonance of the air within the gaps, resonance of the beams, and resonance of the tires. By filling the gaps in the MEJs with engineered chevron support structures we have shown that it is feasible to significantly reduce the noise from MEJs. We performed both experimental and computer evaluations of a noise attenuation system before performing limited testing on the SR 520 bridge. Installation of the treatment on one westbound lane of the east MEJ of the SR 520 bridge proved to be highly effective over the two-month test period. At a distance of 160 feet, we measured a more than 70 percent reduction in audible noise over the noise of background traffic throughout the testing period. Beyond 160 feet the difference between noise from the concrete road surface and from the MEJ became so small that it became very difficult to identify when individual cars crossed the MEJ. While we have shown that the chevron system can be an effective solution to the expansion joint noise issue, we outline further development and testing to extend the durability of the treatment.

Authors:
Reinhall, P., Lipton, J., Thomas, S., Elmadih, W.

Keywords:
Bridge, Expansion joints, Noise control, Noise sources, Sound attenuation, Testing

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Abstract:
Incorporating precast concrete components into bridge piers has the potential to reduce the construction time of a bridge and the negative impacts of that construction on traffic flow. Practical methodologies are needed to design economical and safe piers out of precast concrete components. This research developed force‑based and displacement‑based procedures for the design of both cast‑in-place emulation and hybrid precast concrete piers. The design procedures were developed so that they require no nonlinear analysis, making them practical for use in a design office.The expected damage to piers designed with the procedures in a design‑level earthquake was estimated. The evaluation considered three types of damage to the columns of a pier: cover concrete spalling, longitudinal reinforcing bar buckling, and fracture of the longitudinal reinforcing bars. Both the force‑based and displacement‑based design procedures were found to produce designs that are not expected to experience an excessive amount of damage in a design‑level earthquake.

Authors:
Wacker,J. M., Hieber,D. G., Stanton,J. F., Eberhard,M. O.

Keywords:
Rapid construction, design procedures, hybrid, bridge

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Abstract:
University of Washington researchers developed information tools to increase the speed and efficiency of Washington State Department of Transportation (WSDOT) post-earthquake response and recovery efforts. The researchers upgraded the Pacific Northwest Seismograph Network (PNSN) ground-motion processing software to rapidly generate and disseminate "ShakeMaps," which are maps of earthquake intensity. The researchers also implemented two procedures to estimate the likelihood of slight (or greater) bridge damage; these procedures are based on the intensity of earthquake shaking (obtained from the ShakeMaps) and on each bridge's location, year of construction, and bridge type (obtained from the Washington State Bridge Inventory). The first procedure, developed at the University of Washington, is based on observations of bridge damage from the 2001 Nisqually earthquake. The second procedure is contained in the Federal Emergency Management Agency HAZUS software for predicting the lowest level of damage. Shortly following an earthquake, e-mail and pager alert messages will be sent to WSDOT personnel notifying them of the preliminary earthquake magnitude and epicenter. ShakeMaps and a prioritized list of bridges (ranked by likelihood of bridge damage) will be available on a Web server at the University of Washington and will be pushed to a WSDOT FTP server.

Authors:
Malone,S., Eberhard,M. O., LaBelle,J., Ranf,T.

Keywords:
bridges, damage, earthquakes, fragilities, inspection, ShakeMap, Washington, speed, Washington state, transportation, WSDOT, software, earthquake, bridge, construction, management

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/602.1.pdf http://wsdot.wa.gov/Research/Reports/600/602.1.htm

Abstract:
Increasing traffic volumes and a deteriorating transportation infrastructure have stimulated the development of new systems and methods to accelerate the construction of highway bridges. Precast concrete bridge components offer a potential alternative to conventional reinforced, cast-in-place concrete components. The use of precast components has the potential to minimize traffic disruptions, improve work zone safety, reduce environmental impacts, improve constructability, increase quality, and lower life-cycle costs. This study compared two precast concrete bridge pier systems for rapid construction of bridges in seismic regions. One was a reinforced concrete system, in which mild steel deformed bars connect the precast concrete components and provide the flexural strength of the columns. The other was a hybrid system, which uses a combination of unbonded post-tensioning and mild steel deformed bars to make the connections. A parametric study of the two types of systems was conducted using nonlinear finite element models to investigate the global response and likelihood of damage for various frame configurations. On the basis of this study, a practical method was developed to estimate maximum seismic displacements from the cracked section properties of the columns, the elastic design displacement response spectrum, and the base-shear strength ratio. The results of the global nonlinear finite element analyses suggest that the systems have the potential for good seismic performance. Further analytical and experimental research is needed to investigate the constructability and seismic performance of the connection details.

Authors:
Hieber,D. G., Wacker,J. M., Eberhard,M. O., Stanton,J. F.

Keywords:
Alternative, bridge, bridges, columns, concrete, concrete bridge, connections, constructability, construction, cost, costs, damage, design, developed, development, environmental, environmental impact experimental, finite element, highway, impact, impacts, infrastructure, methods, models, performance piers, precast, precast concrete, prestressed concete, quality, Rapid construction, Regions, reinforce concrete, research, response spectra, response spectrum, safety, seismic, seismic performance, steel strength, Study, substructures, System, systems, traffic, traffic volumes, trasportation, volume

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/611.1.pdf http://wsdot.wa.gov/Research/Reports/600/611.1.htm

Abstract:
More extensive use of precast concrete components, which are fabricated off-site and then connected on-site, could allow bridges to be constructed more rapidly. The increased use of precast components in bridges also promises to increase work-zone safety and reduce environmental impacts for bridges that span waterways. This report discusses precast concrete systems that have been used for rapid bridge construction outside of Washington State and evaluates whether they are suitable for use within Western Washington. The report also identifies key features that are important for successful precast concrete system applications. Information on previously used systems was gathered through an extensive review of published literature. Washington State Department of Transportation (WSDOT) design and construction engineers, precast concrete producers, and bridge contractors were also consulted to obtain their input on the positive and negative aspects of applied systems. Most applications have been used in areas of low seismic potential. By contrast, Western Washington is subject to strong earthquakes. Because precast systems contain connections, and connections are typically vulnerable to seismic loading, a qualitative evaluation of the expected seismic performance of each system was deemed necessary. The researchers identified four types of precast concrete superstructure systems: full-depth precast concrete panels, partial-depth precast concrete panels, prestressed concrete multibeam superstructures, and preconstructed composite units. The four systems appear to have acceptable seismic behavior, but there are concerns associated with constructability and durability. Precast concrete substructure systems have received much less attention than have superstructure systems. The use of precast substructure components can provide significant time savings by eliminating the time needed to erect formwork, fix steel, and cure concrete in the substructure. The success of the system depends strongly on the connections, which must hae good seismic resistance, have tolerances that allow easy assembly, and be suitable for rapid construction.

Authors:
Hieber,D. G., Wacker,J. M., Eberhard,M. O., Stanton,J. F.

Keywords:
bridge, bridges, concrete, construction, multibeam superstructures, precast concrete, precast substructures, prestressed concrete, Rapid construction, state-of-the-art, systems, safety, environmental, environmental impact, impacts, span, Washington, Washington state, applications, transportation, WSDOT, design, seismic, earthquake, seismic loading, evaluation, performance, superstructure, prestressed, seismic behavior, constructability, durability, steel, resistance

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/594.1.pdf http://wsdot.wa.gov/Research/Reports/500/594.1.htm

Abstract:
Cotton duck bearing pads (CDP) are sometimes used to support loads and accommodate movements and rotations at bridge bearings. CDP are preformed elastomeric pads consisting of thin layers of elastomer interlaid with fabric, and they are manufactured under Military Specifications with limited guidance from the AASHTO. The behavior of these CDP bearing pads was experimentally evaluated to establish design models for predicting this behavior, to determine the variation in behavior expected with different bearing pad manufacturers, and to develop design recommendations. This research is a follow-up study of an earlier research program sponsored by Arkansas State University.CDP bearing pads from three different manufacturers were tested, and the test program included dynamic and static (or monotonic) tests of bearings in shear, compression,and rotation. In general, the static tests were used to evaluate strength, stiffness, deformation limits, and general pad behavior. The dynamic tests examined durability and performance under repeated loading and deformation.The results of this test program were used to develop design recommendations, and an appendix includes a draft of proposed wording for modification of the AASHTO LRFD Specifications to include these design recommendations. In addition, a spreadsheet was developed in Microsoft EXCEL to accomplish the calculations necessary to complete the design.

Authors:
Lehman,D. E., Roeder,C. W., Larsen,R., Curtin,K.

Keywords:
cotton duck bearing pads, CDP, bridge bearings, bridge design, loads, bridge, specifications, specification, behavior, design, models, research, program, tests, strength, durability, performance

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/569.1.pdf http://wsdot.wa.gov/Research/Reports/500/569.1.htm

Abstract:
The Service Patrol pilot demonstration in Seattle and Tacoma was managed by the Washington State Department of Transportation (WSDOT) and operated by Washington State Patrol (WSP) cadets and contracted registered tow truck operators (RTTOs). Two other roving services, not funded as part of this pilot effort but included to a limited extent in this evaluation, were the roving patrol service provided by WSDOT on the SR 520 and I-90 floating bridges and the privately sponsored motor assistance vehicle from AAA's RescueVan. The evaluation examines how the similarities and differences among the different service delivery modes (e.g., the intensity of deployment, equipment choices, service delivery, costs) affect the impact of the Service Patrol operation on traffic conditions (e.g., reductions in delay) and the level of motorist satisfaction. This report also discusses feedback by the agencies participating in the Service Patrol program on institutional and operational issues that contribute to or hinder the success of the program. Operational characteristics and operating statistics are reported to convey factors that describe program effectiveness. The results of the study indicate that the use of a combination of service providers has benefits that no single provider can duplicate, and the cost implications of changing the program are small enough that any potential savings would be fairly minor. The pilot project resulted in a variety of intangible benefits, such as improved interagency coordination and cooperation, more efficient utilization of personnel, and a better understanding of each partner's roles and contributions toward congestion relief. The positive viewpoint toward the Service Patrol was uniform, regardless the service mode. Therefore, no significant changes to the existing pilot program are recommended at this time.

Authors:
Nee,J., Hallenbeck,M. E.

Keywords:
service patrols, incident response time, traffic delay, traffic safety, research, seattle, Washington, Washington state, transportation, WSDOT, truck, evaluation, floating bridge, bridges, bridge, costs, cost, traffic, condition, program, statistics, benefits, benefit, congestion

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Abstract:
This annual meeting covered a wide variety of transportation issues. Bridge and Design issues were discussed, material and pavement specification, as well as strategic planning and traffic control.

Authors:
Anderson,K. W.

Keywords:
69th, Annual, bridge, control, design, Meeting, pavement, planning, specification, strategic planning, traffic, traffic control, transportation, TRB

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Abstract:
This study investigated retrofitting measures for improving the seismic performance of existing multi-column bridge bents. Experimental tests were conducted on 1/4.5-scale footing and column assemblages which incorporated details that were selected to represent deficiencies present in older bridges. Various retrofit measures for the bents were evaluated. The specimens were subjected to increasing levels of cycled inelastic lateral displacements under constant axial load. Specimen performance was evaluated on the basis of load capacity, displacement ductility, strength degradation and hysteretic behavior.Tests on the as-built specimens resulted in severe cracking in the footings due to insufficient joint shear strength in the column/footing connections. However, due to structural redundancy, the bents continued to resist lateral loads until eventual bent failure occurred as a result of flexural hinge degradation in the columns.Measures developed previously for retrofitting single-column bent bridges were found to be effective in improving the performance of the footings and columns. When all substructure elements were retrofitted, a ductile bent response was obtained. Retrofitting only some of the substructure elements resulted in incremental improvements in performance according to the number of elements retrofitted. While extensive damage occurred in the unretrofitted elements, the damaged regions continued to transfer forces during testing, enabling a stable bent response until failure occurred within one or more of the retrofitted elements.The addition of a stiff link beam just above the footings was found to be effective in preventing damage in the footings during testing, and a reasonably ductile bent response was achieved. Because the link beam retrofit may not require retrofitting of the footings, this strategy may be a very cost-effective approach for retrofitting multi-column bents.

Authors:
McLean,D. I., Kuebler,S. E., Mealy,T. E.

Keywords:
seismic retrofitting, reinforced concrete, bridge, substructures, multi-columns bents, research

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Abstract:
Current seismic design criteria for highway bridges generally require that the effects of earthquake loading be evaluated using either an equivalent static load approach for simple bridges or a dynamic analysis for more complex bridges. These provisions usually provide detailed explanations and commentaries on techniques which are judged to be suitable for static and dynamic modeling of the bridge superstructure and supporting columns or piers. There is, however, a significant lack of guidance on exactly how the boundary conditions and soil-structure-interaction should be incorporated into the model.The purpose of this study is to present a simple analytical model of pile and pile group foundations for use as boundary conditions in a numerical model for seismic analysis of highway bridges. Both the axial and lateral response are considered. This simple model consists of a set of springs, dashpots, and masses for each degree-of-freedom on a pile, and it is based upon the Winkler hypothesis. The spring behavior is established by using the finite element method for static load conditions. The lumped dashpot constants and masses are based on realistic approximations. The effect of a sliding interface, nonlinearity of the soil and geometric, hysteresis, and viscous damping of the soil have been considered.The p-y curves for lateral and axial vibration of single piles of 0.457m (18") and 0.610m (24") diameter based on plane analysis for different depths have been presented. Similar curves for direct lateral, shear-lateral, and axial vibrations have also been presented for two-pile groups with three different spacings.Using these p-y curves, pile responses have been obtained which have been compared with those obtained from a rigorous analysis. Good agreement has been observed for a single pile response. The comparison justifies the use of this simple model.

Authors:
Modak,S., Cofer,W. F.

Keywords:
bridge, earthquake, piles, group, finite element

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Abstract:
Lap splices in reinforced concrete members typically consist of bars overlapped and placed in contact with each other. In the case of a large-diameter foundation shaft connecting to a smaller-diameter column, it is not possible to have the longitudinal bars be continuous, nor is it possible to provide a standard lap splice; instead an offset or noncontact lap splice of the longitudinal bars is required. With a noncontact lap splice, transfer of forces from one spliced bar to the other occurs through the surrounding concrete, and transverse reinforcement is typically required to provide satisfactory splice performance. Current code provisions on noncontact lap splices are very limited.This study experimentally investigated the behavior of noncontact lap splices in bridge column-shaft connections. Tests were performed on near full-scale panel specimens, representing a cross-section of a column-shaft connection, and on 1/4 scale column-shaft specimens under both monotonic and cyclic loading. Variables investigated included lap splice length, lapped bar spacing, and spacing of transverse reinforcement. Specimen performance was evaluated in terms of load capacity, failure mechanism, and strength degradation.Two-dimensional and three-dimensional truss models were developed to predict, the behavior of noncontact lap splices. Experimental results supported the proposed behavioral models. Inclined cracks developed in the concrete which defined compression struts running between the offset lapped bars. Transverse reinforcement was required to provide equilibrium to the struts. Tests on specimens detailed based on the proposed models resulted in no strength degradation or slippage of the lapped reinforcing bars even when subjected to cyclic loading. Equations were proposed for the design of noncontact lap splices, including recommendations for required overall lap length and transverse reinforcement.

Authors:
McLean,D. I., Smith,C. L.

Keywords:
reinforced concrete, bridge, reinforcing splices, columns, foundation shafts, research

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Abstract:
In the seismic design criteria for highway bridges, there is a significant lack of guidance on ways to incorporate the effect of soil-structure interaction in determining seismic response. For this study, a simple analytical model for pile and pile group foundations is presented for use in dynamic modeling of bridge superstructures. Both the axial and lateral pile response is considered. This simple model consists of a set of nonlinear springs, dampers, and masses for each degree-of-freedom of the pile, and it is based on the Winkler hypothesis. The spring behavior was established by using the finite element method for static load conditions and a typical soil from Washington state. The lumped damping constants and masses were based on realistic approximations. The p-y and t-z curves for single piles and two-pile groups were presented for two pile diameters. Using these curves as near-field Winkler elements, combined with established far-field elements, the dynamic response of a single pile when subjected to a half-sine impulse load was compared to that of a more rigorous, nonlinear, three-dimensional finite element analysis. Close agreement was observed. For design, suggestions were made on ways to develop an approximately equivalent foundation model consisting of a single mass, spring, and damper.

Authors:
Cofer,W. F., Modak,S.

Keywords:
bridge, earthquake, piles, group, finite element

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Abstract:
Many retrofit measures have been proposed and then implemented into existing highway bridges. The goal of seismic strengthening is not intended to retrofit a bridge to be "earthquake-proof", but to minimize the likelihood of a structural collapse. An amount of acceptable damage may occur during a design level earthquake. The combination of retrofit measures and the acceptable damage greatly complicates the structural properties for a bridge. It is necesary to use analytical and experimental means to verify the effectiveness of various retrofit combinations.The objectives of this research are: (1) to investigate analytically the feasibility and advantages of applying the retrofit measures developed for single-column bent bridges to multi-column bend bridges; (2) to evaluate analytically the effects and benefits of current column retrofit strategies for multi-column bridges and propose the most effective measures for strengthening bridges; (3) to evaluate the performance of earthquake restrainers and find the change of seismic load and displacements cause by their installation.To achieve the objectives, an existing nonlinear dynamic bridge analysis program with elastic-perfectly plastic column behavior and a conventional hysteresis model was modified in order to include softening behavior and a more realistic hysteresis rule for cyclic loading.Both two- and three-dimensional structural models for two actual bridges from Washington were analyzed by inputting a typical seismic record. The two-dimensional models were used to evaluate column retrofitting measures, and the three-dimensional model was used to evaluate the performance of longitudinal earthquake restrainers. Both artial and full column retrofit stratgies were shown to result in decreased maximum earthquake response and decreased plastic deformation of columns for the bridge bent compared to the case without retrofitting. Therefore, it was concluded that the partial column retrofit strategies were feasible after a ductility capacity of the bridge is exactly defined. The opening displacements at expansion joint hinges were decreased due to the installation of longitudinal restrainers. Additionally, the redistribution of earthquake forces caused by their installation was not significant. Many retrofit measures have been proposed and then implemented into existing highway bridges. The goal of seismic strengthening is not intended to retrofit a bridge to be "earthquake-proof", but to minimize the likelihood of a structural collapse. An amount of acceptable damage may occur during a design level earthquake. The combination of retrofit measures and the acceptable damage greatly complicates the structural properties for a bridge. It is necessary to use analytical and experimental means to verify the effectiveness of various retrofit combinations.

Authors:
Cofer,W. F., McLean,D. I., Zhang,Y.

Keywords:
bridge, earthquake, retrofit, analysis, columns

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Abstract:
Currently, two commonly used restrainer design methods are those mandated by the American Association of State and Highway Transportation Officials (AASHTO) and the California Department of Transportation (CALTRANS). To evaluate these methods and perhaps develop a new method, the Washington State Department of Transportation (WSDOT) sponsored this study.Using sample WSDOT designs and seismic retrofitting guidelines from WSDOT and CALTRANS, the researchers developed a model of a two-frame bridge with a single in-span hinge. The nonlinear response of the bridge was studied to determine the maximum opening experienced at the in-span hinge and the maximum relative displacements at the abutments.To identify the parameters most important in restrainer design and in predicting the unrestrained maximum relative abutment displacements, the researchers varied eleven parameters. The parametric study identified the parameters that significantly influenced the maximum relative hinge displacement (MRHD) and the maximum relative abutment displacements (MRAD). Currently, two commonly used restrainer design methods are those mandated by the American Association of State and Highway Transportation Officials (AASHTO) and the California Department of Transportation (CALTRANS). To evaluate these methods and perhaps develop a new method, the Washington State Department of Transportation (WSDOT) sponsored this study.Using sample WSDOT designs and seismic retrofitting guidelines from WSDOT and CALTRANS, the researchers developed a model of a two-frame bridge with a single in-span hinge. The nonlinear response of the bridge was studied to determine the maximum opening experienced at the in-span hinge and the maximum relative displacements at the abutments.The AASHTO empirical seat width equation and the CALTRANS restrainer design method were compared with the results of nonlinear time history analysis. The empirical seat width equation produced conservative results while the CALTRANS method produced inconsistent results, a large amount of scatter and some significantly unconservative values.Using the results of the parametric study, the researchers developed a new restrainer design method that predicted the MRHD much more accurately than the CALTRANS method. The researchers also developed a method for estimating the unrestrained MRAD.

Authors:
Trochalakis,P., Eberhard,M. O., Stanton,J. F.

Keywords:
bridge, design, hinge, earthquake, evaluation, restrainers

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Abstract:
The Washington State Department of Transportation (WSDOT) is currently retrofitting many older bridges to prevent their superstructures from unseating during earthquakes. In bridges whose simply supported spans have inadequate bearing lengths, WSDOT most frequently connects adjacent spans with high-strength rod restrainers. The study described in this report was undertaken to determine whether restrainers in this manner are effective in preventing span unseating and to develop a method for identifying vulnerable simply supported spans. A companion report considered the design of seismic restrainers for in-span hinges.The researchers developed a nonlinear analytical model of a four-span, simply supported, prestressed concrete bridge. Variations of this model were subjected to four ground motions to determine the maximum relative displacements between the simply supported spans and their supports. The maximum relative displacements at the piers depended most on the bearing friction resistance, the earthquake motion, and the size of the joints in the deck. The maximum relative displacements at the abutments depended most on the bearing resistance and the earthquake motion.Based on the results of the parametric study, the researchers developed a new method to estimate the susceptibility of bridges to unseating of simply supported spans. The researchers also found that restrainers connecting adjacent spans are ineffective in reducing the relative displacements between the superstructure spans and their supports.

Authors:
Trochalakis,P., Eberhard,M. O., Stanton,J. F.

Keywords:
bridge, design, span, unseating, earthquake, evaluation

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Abstract:
This report summarizes WSDOT's 10 year of experience with "epoxy" and "Methl Methacrylate" (MMA) thin polymer bridge deck overlays.

Authors:
Wilson,D. L., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge deck overlay, bridge deck repairs, Deck, evaluation, overlay, overlays, polymer, polymer concrete, thin overlay, WSDOT

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Abstract:
This study investigated retrofitting measures for improving the seismic performance of the substructures of existing bridges. Retrofit measures for both pile-supportes and spread footings were investigated. Experimental tests were conducted on 1/3-scale footing and column assemblages which incorporated details that were selected to represent deficiencies present in older bridges. Retrofit measures were applied to both the columns and footings. The speciments were subjected to increasing levels of cycled inelastic lateral displacements under constant axial load. Specimen performance was evaluated on the basis of load capacity, displacement ductility, strength degradation and hysteretic behavior.Tests on the as-built speciment resulted in a brittle failure due to insufficient joint shear strength in the column/footing connection. An added reinforced concrete overlay provided an effective retrofit for the as-built footings. The overlay resulted in increased shear resistance, allowed for the addition of a top mat of reinforcement to provide negative moment strength, and increased the positive moment capacity by increasing the effectve depth of the pile cap. All retrofitted specimens developed plastic hinging in the columns with a resulting ductile response under the simulated seismic loading. Special detailing was required in the column lap splice regions in order to maintain the integrity of the splices. In specimens that were overturning critical, increased overturning resistance was provided by enlarging the footing plan size, by providing additional piles, or by providing tie-downs through the footing.

Authors:
McLean,D. I., Saunders,T. D., Hahnenkratt,H. H.

Keywords:
seismic retrofitting, reinforced concrete, bridge, substructures, research

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Abstract:
An engineering team from the University of Washington (UW) evaluated the seismic vulnerability of the Alaskan Way Viaduct, located in Seattle, Washington. This report presents the evaluation of a typical three-bay unit that was designed by The City of Seattle Engineering Department (SED). The evaluation team performed response-spectrum analyses and nonlinear analyses for the fixed-base condition. The team considered a widely used soft-soil spectrum and worst-case, site-specific spectra. Wherever possible, the UW team evaluated the vulnerability for each failure mode following procedures proposed; by the Applied Technology Council; and by researchers at the University of California, San Diego.The evaluation team found that the vulnerability of the Alaskan Way Viaduct exceeds that of bridges built to current standards. The vulnerability is a result of a combination of two factors: (1) the design ground motion would strongly excite the viaduct; and (2) many of the structural components lack the ductility required by current standards. The following deficiencies were identified as the most critical.*The lower-story columns have inadequate transverse reinforcement, and could fail in shear before they develop their flexural capacity.*The first- and second-story joints have inadequate confinement reinforcement, and during strong ground motions, they could experience a diagonal-tension failure.*If the base of the lower-story columns develop their flexural capacity, the footings could fail in shear.

Authors:
Knaebel,P., Eberhard,M. O., de la Colina,J.

Keywords:
bridge, earthquake, evaluation, reinforced concrete

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Abstract:
An engineering team from the University of Washington (UW) evaluated the seismic vulnerability of the Alaskan Way Viaduct, located in Seattle, Washington. This report presents the evaluation of a typical three-bay unit that was designed by WSDOT. The evaluation team performed response-spectrum analyses and nonlinear analyses for both fixed-base and pinned-base conditions. The team considered a widely used soft-soil spectrum and worst-case, site-specific spectra. Wherever possible, the UW team evaluated the vulnerability to each failure node following two or three procedures, including those proposed by the Applied Technology Council (1983) and Priestley, Seible, and Chai (1992).The evaluation team found that the vulnerability of the Alaskan Way Viaduct exceeds that of bridges built to current standards. The vulnerability is a result of a combination of two factors: (1) the ground motion is likely to strongly excite the viaduct; and (2) many of the WSDOT unit's structural components are likely to behave in a brittle manner. The following deficiencies were identified as the most critical.*The first-story column-reinforcement splices are too short, they have too little confinement reinforcement, and they are located in regions likely to experience large ductility demands.*The column/beam joints have inadequate confinement reinforcement, and during strong ground motions, they could experience a diagonal tension failure.*The shear strength of the first-story columns is marginal.*If the first-story columns develop their flexural capacity during an earthquake, the pile-supported footings could fail in shear.

Authors:
Eberhard,M. O., de la Colina,J., Ryter,S.

Keywords:
bridge, earthquake, evaluation, reinforced concrete

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Abstract:
This study was part of a Washington State Department of Transportation (WSDOT) program to assess the vulnerability of multiple-span highway bridges built before 1984. During the first series of static tests (Phase I), discussed in a previous report, a three-span, reinforced concrete bridge was subjected to large lateral loads. In Phase II, described in this report, the researchers greatly reduced the resistance that the abutments provided so that they could evaluate the lateral-load resistance of the piers. The researchers then subjected the piers to large, transverse cyclic displacements with drift ratios of 0.5, 1.0, 2.0, and 3.0 percent.The piers resisted repeated loadings to a force equal to one third of the bridge's weight. The envelope to the pier's hysteretic response indicated that the system yielded at a drift ratio of 0.7 percent. Whereas the top of the columns spalled at large drift ratios, the damage to the bottom of the columns was limited to flexural cracks. The pier's measured response was compared to that calculated by the researchers, the California Department of Transportation, and the WSDOT. The calculated responses were found to be strongly sensitive to the assumed steel and soil properties. On the basis of the experience gained in performing the tests, the researchers made recommendations for those planning to perform future tests of large structures. In -addition, while acknowledging the limitations of a single series of static tests, the researchers concluded that (1) the tests should serve as a benchmark against which to evaluate proposed analytical models, (2) at an effective acceleration of 0.2g, the seismic damage to the isolated bridge would probably be minor, (3) at an effective acceleration of 0.4g, the piers would likely sustain heavy damage, and (4) the WSDOT should investigate the influence of soil properties on column damage to determine when geotechnical tests are warranted.

Authors:
O'Donovan,T., Eberhard,M. O., MacLardy,J. A., Marsh,M. L.

Keywords:
bridge, earthquake, piers, reinforced concrete, tests, modeling, lateral loads

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Abstract:
This study investigated the seismic response of the westbound lanes of I-90 crossing Mercer Slough. Mercer Slough is filled with a very soft, thick peat deposit. Both linear and nonlinear dynamic analyses were performed, including special analyses, linear time-history analyses and nonlinear time-history analyses. Variables considered in the analyses included different column and foundation stiffness, different seismic input, different simultaneous seismic input, and non-linear joint behavior. The response of the bridge was found to be extremely sensitive to seismic input and, to a lesser extent, foundation stiffness. Consideration of nonlinear effects tended to lessen the bridge response. The analyses also indicated that a long, loosely connected bridge, such as that crossing the Mercer Slough, can be adequately analyzed using a fairly short section of the bridge. All of the different analyses indicated that elements in the bridge would probably be close to or exceed their capacity during an earthquake. Problem areas which were identified included the inability of the expansion joints to sustain large relative displacements and the possible overloading of the columns in flexure.

Authors:
McLean,D. I., Cannon,I. B. S.

Keywords:
bridge and construction, bridge, seismic responses, peat, dynamic wheel loadings analysis, earthquake

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Abstract:
Transverse reinforcement in bridge columns normally consists of spiral reinforcement in columns with circular cross-sections and tied reinforcement in columns with square or rectangular cross-sections. The circular shape of spiral reinforcement in inherently efficient in providing confinement to the concrete core and restraint of longitudinal bar buckling. In contrast, rectangular columns require cross-ties and/or overlapping ties in addition to the perimeter tie in order to provide adequate confinement and restraint of bar buckling. As an alternative reinforcing scheme, interlocking spiral reinforcement has been used in California for columns with rectangular cross-sections. However, several important design elements are not addressed in th Caltrans specification, and the performance of columns with interlocking spirals has not been fully established.This study experimentally investigated the seismic behavior of columns incorporating interlocking spirals under flexural, shear and torsional loadings. The main tests were performed on approximately 1/5-scale column speciments subjected to incraeasing levels of cycled inelastic displacements under constant axial load. Rectangular and oval cross-sections with either two interlocking spirals or conventional ties were investigated. Variables studies included the performance of interlocking spirals compared to ties, the amount of spiral overlap, an the size of longitudinal bars required in the overlap region to maintain spiral interlock.Columns with interlocking spirals performed as well or better than columns with ties, despite approximately 50% more transverse reinforcement being provided in the tied columns. Test results indicated improved performance when the center-to-center spacing of interlocking spirals was not greater than 0.6 times the spiral diameter. At least four longitudinal bars of approximately the same size as the main longitudinal reinforcement are required in the overlap regioin to maintain spiral interlock. Procedures were developed for predicting the axial, shear, flexural and torsional strengths of columns with the interlocking spirals.

Authors:
McLean,D. I., Buckingham,G. C.

Keywords:
seismic design, bridge, columns, reinforced concrete, transverse reinforcement

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Abstract:
The response of bridges when subjected to seismic excitation may be significantly influenced by the dynamic properties of their foundations. With current design practice, foundation elements are typically considered as elastic springs without consideration of material and radiation damping. The objectives of this research were to identify general foundation models that are suitable for modeling soil-structure interaction in seismic bridge analysis, to modify an existing nonlinear seismic bridge analysis computer program to include a new element capable of representing such models, and to conduct a parametric study to assess the effect of the nacres energy dissipation mechanisms on the response of bridge substructures. For spread footing foundations, three different models were identified and applied to a typical two-column bridge bent. The seismic response for each model was compared with conventional elastic and fixed-base models. Several soil stiffness values and earthquake records were considered for analysis. Maximum values of displacement, plastic hinge rotation, and cumulative plastic hinge rotations were noted and compared. It was concluded that the use of the foundation models can produce an important change in the bridge response when compared to that of the fixed-based models, depending on the frequency and content of the earthquake and the stiffness of the soil. The effects of radiation damping were observed to be insignificant for foundations on stiff soil, but important for those on soft soil. In addition, the performance of the simpler damped foundation models was found to be quite similar to that of more complex models.

Authors:
Cofer,W. F., McLean,D. I., McGuire,J. W.

Keywords:
structures, seismic, bridge, earthquake, soil-structure interaction, foundation, analysis, modeling

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Abstract:
The response of bridges when subjected to seismic excitation may be significantly influenced by the dynamic properties of their foundations. With current design practice, foundation elements are typically considered as elastic springs without consideration of material and radiation damping. The objectives of this research were to identify general foundation models that are suitable for modeling soil-structure interaction in seismic bridge analysis, to modify an existing nonlinear seismic bridge analysis computer program to include a new element capable of representing such models, and to conduct a parametric study to assess the effect of the increased energy dissipation mechanisms on the response of bridge substructures. For spread footing foundations, three different models were identified and applied to a typical two-column bridge bent. The seismic response for each model was compared with conventional elastic and fixed-base models. Several soil stiffness values and earthquake records were considered for analysis. Maximum values of displacement, plastic hinge rotation, and cumulative plastic hinge rotations were noted and compared. It was concluded that the use of the foundation models can produce an important change in the bridge response when compared to that of the fixed -based models, depending on the frequency and content of the earthquake and the stiffness of the soil. The effects of radiation damping were observed to be insignificant for foundations on stiff soil, but important for those on soft soil. In addition, the performance of the simpler damped foundation models was found to be quite similar to that of more complex models.

Authors:
Cofer,W. F., McLean,D. I., McGuire,J. W.

Keywords:
bridge, earthquake, soil-structure interaction, foundation, analysis, modeling

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Abstract:
The construction and pressure testing of a field installation of ADS HDPE corrugated PVC sewer pipe is documented in this report.

Authors:
Anderson,K. W., Gubbe,J.

Keywords:
bridge, construction, drainage, facilities, maintenance, pipes, plastic, pressure, PVC, Washington

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Abstract:
The major objective of this project was to develop a post-earthquake emergency response plan to WSDOT bridge management. Three types of seismic events was considered in the development of the plan. Inspection forms were developed for the three-stage inspection process. For events other than minor earthquakes under favorable weather and lighting conditions, existing resources appear to be inadequate. Recommendations for improving the readiness of the WSDOT bridge management are provided.

Authors:
Reed,D., Wang,J.

Keywords:
traffic surveillance and control, earthquake, emergency response planning, bridge

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Abstract:
This study was part of a Washington State Department of Transportation (WSDOT) program to assess the vulnerability of highway bridges built before 1984. Researchers applied slowly-varying transverse loads to a three-span, reinforced concrete bridge, including the superstructure, piers, and abutments. The purpose of the test was to measure the transverse stiffness of the bridge and to estimate each support's contribution to stiffness. The researchers also evaluated analytical models by comparing the calculated and observed responses. The bridge was extremely stiff and strong. In two cycles to a load equal to 45 percent of the bridge's weight, the maximum bridge displacement was 0.15 inch. During these cycles damage was minimal. At a load equal to 65 percent of the bridge's weight, the pier displacement was 0.30 inch. After the bridge had been excavated, the stiffness decreased to 15 percent of its original stiffness. The stiffness further decreased to 8 percent of the initial stiffness after the superstructure had been isolated from the abutments. The University of Washington (UW), California Department of Transportation (CALTRANS) and WSDOT models underestimated the stiffness of the bridge in its initial state. The UW model probably overestimated the resistance of the polystyrene at the abutments and underestimated the stiffness of the soil at the wingwalls. The CALTRANS model was too flexible because it neglected the resistance of the bearing pads and polysterene, and underestimated the soil stiffness. The researchers concluded that (1) the test can serve as a valuable benchmark against which to evaluate proposed seismic-evaluation procedures and models, (2) bridges that are similar to the test bridge are not highly vulnerable to transverse motions, (3) complex soil modeling is not justified if soil test data are not available, and (4) nonlinear analysis was necessary to reproduce the details of the observed response.

Authors:
Eberhard,M. O., MacLardy,J. A., Marsh,M. L., Hjartarson,G.

Keywords:
bridge and construction, bridge, earthquake, reinforced concrete, tests, modeling, lateral loads

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Abstract:
Dames & Moore And their subcontractor, Inco Engineers, have prepared this Manual of Practice for conducting bridge foundation-soil interaction analyses. The manual is intended to assist engineers in the Bridge Design office at the Washington State Department of Transportation (WSDOT) who perform dynamic analysis of bridge-foundation systems. The primary purpose of the manual is to present practical and accurate methods of estimating the foundation stiffness matrices for abutment or pier foundations supported on footings or piles. These matrices are needed for soil-structure interaction analysis to more accurately determine the seismic loads acting on the bridge superstructure and on the abutment and pier foundations.This Manual of Practice consists of two volumes. Volume I presents five bridge example problems:1. Coldwater Creek2. Deadwater Slough3. Ebey Slough4. Northup Way5. FHWAThe first four examples are actual WSDOT bridges and the fifth example is a fictitious bridge that appeared in a 1991 FHWA course notebook on seismic design of highway bridges.Volume II presents the input and output files of the SEISAB computer program for the dynamic soil-structure interaction analysis of bridges. The SEISAB computer program is currently used by WSDOT in the seismic design of Washington state bridges.Dames & Moore recommends the FHWA and Novak methods to estimate bridge foundation stiffness matrices. These methodologies are presented in detail in the Coldwater Creek example problem in Volume I. In this example, the basic theory and relevant equations or inputs for implementing these methodologies are provided first and are immediately followed by their application to the Coldwater Creek bridge. The appropriate equations or inputs from the FHWA and Novak methodologies presented not the Coldwater Creek example problem are identified and applied in the other four bridge example problems. Volume I also contains three appendices. The basis for the recommendation of the FHWA and Novak methods is provided in Appendix A, which is a reproduction of the 1992 Dames & Moore report to WSDOT on the evaluation of methods to estimate foundation stiffnesses. Appendix B consists of selected pages from the BMCOL 76 computer program user guide; this computer program, which computes the load-deflection and moment-rotation curves for single piles, is part of the FHWA methodology. Appendix C presents the method for transforming the foundation stiffness matrices from one coordinate system to another. This transformation process is important because the coordinate systems assumed in the FHWA and Novak methods are generally different and therefore are not necessarily the same as the SEISAB coordinate system. Coordinate transformations are also discussed in the ColdWater Creek example problem.

Authors:
Dames & Moore- Inca Engineering

Keywords:
analysis, bridge, bridge design, bridge foundation, bridges, computer, computer program, design, equations, evaluation, Foudation-Soil, foundation, foundation stiffness, highway, interaction, loads, manual, methodology, methods, piles, program, seismic, seismic design, soil-structure interaction, superstructure, System, systems, transportation, volume, Volumes I & II, Washington, Washington state, WSDOT

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Abstract:
The University of Washington (UW) team reviewed the Washington State Department of Transportation (WSDOT) report titled 'Earthquake Analyses of the Alaskan Way Viaduct' and performed an independent assessment of two typical sections of the structure. Additional analyses were performed to investigate the influence of some factors that were not considered in the WSDOT report. The input motion and geotechnical characteristics assumed in the WSDOT report were consistent with the information available to the WSDOT and the UW. However, the paucity of information available regarding the seismological risk and the subsoil conditions precluded the possibility of reliability estimating the input motion, foundations stiffness, foundation capacities, and potential for liquefaction. Inspection of the structural plans suggested that timber-concrete spliced piles in the section of the structure built by WSDOT might be particularly vulnerable. The elastic dynamic models generated by WSDOT and those constructed for this study were found to give comparable natural periods in the first three modes. Those in the higher modes differed because of the disparate ways in which the structures were modeled. However, the higher modes provided only a small portion of the total response, so the differences in calculated response were small. For the WSDOT designed part of the structure, g-ratings and dynamic code ratios were established by assuming that the reinforcement would reach its yield strength. The present study found the structure to be generally weaker than did the WSDOT study. Some of the ratings showed a consistent relationship with those given by the WSDOT study, while others showed considerable scatter. Regardless of the resolution of the discrepancies, both analyses indicated that the demands on structural members would be likely to greatly exceed their capacities. The main shortcomings in the structure appeared to be inadequate confinement steel and development lengths that were too short. Because no distress was observed after the 1965 Seattle earthquake, these calculations are undoubtedly conservative. However, the response of those brittle details cannot be predicted reliably without further investigation. The University of Washington team is proposing further study to verify seismic safety of the structure.

Authors:
Brown,C., Eberhard,M. O., Kramer,S. L., Roeder,C. W., Stanton,J. F.

Keywords:
bridge, reinforced concrete, earthquake, foundation

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Abstract:
The Washington State Department of Transportation is conducting experimental field evaluations of selected polymer concrete thin (1/4 inch) overlays. The polymer concrete material is manufactured by private industry firms and installed on selected bridge decks under standard WSDOT construction contracts. Approximately 24 bridges will be involved in the experiment; eight of these are included in federal participating construction projects as experimental features.A polymer concrete thin overlay, The Conkryl Broadcast System (methlmethacrylate), was applied to the deck of the South 154th Street Overcrossing, Bridge No. 5/523, under Contract No. 3354, SR 405 Tukwila to South Renton HOV Lanes. This bridge is a prestressed girder bridge located on the mainline I-5 at the intersection with I-405 in Seattle, Washington.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge deck repairs, bridge decks, bridges, concrete, construction, contracts, Deck, evaluation, experimental, HOV, HOV lanes, lanes, overlay, overlays, polymer, polymer concrete, prestressed, project, seattle, thin overlay, transportation, Washington, Washington state, WSDOT

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Abstract:
The seismic performances of three retrofitted and one control, half scale, circular, reinforced concrete columns were studied. The columns were 10ft. high and 18 in. diameter cantilevers. The longitudinal flexural steel was spliced to the foundation dowels just above the fixed base. A concentric axial load of 20 fc Ag was continually applied during testing. The free ends of the cantilevers were translated to produce a maximum displacement of four times than necessary to produce yield in the longitudinal reinforcing steel. This loading was repeated with both positive and negative displacements in a quasi-static manner until the lateral forces required to produce these displacements approached zero. The measure of seismic durability used was the number of such cycles that a column sustained before losing structural integrity. The arrangement was intended to model that of bridge columns constructed during the 1960's. Three columns were retrofitted with prestressed, externally located circular hoops at intervals along the lower 4 ft. The spacing and size of these ties varied from column to column. The control column sustained less than two cycles before losing structural integrity; the retrofitted columns sustained a minimum of twelve cycles.

Authors:
Coffman,H. L., Marsh,M. L., Brown,C.

Keywords:
bridge and construction, reinforced concrete, bridge, columns, earthquake resistance, retrofitting, repair, splices, hoops, confined concrete, ductility, infrastructure, plastic hinges, inelastic deformations

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Abstract:
This report documents a study that determined the effectiveness and cost of both previously used and proposed bridge superstructure seismic retrofit methods, including longitudinal joint restraining, transverse bearing restraining, bearing seat extension, replacement of vulnerable bearings with conventional bearings, and replacement with base isolation bearings. In addition, a procedure was developed for systematically prioritizing the state's bridges for seismic retrofitting on the basis of their importance as lifelines and their vulnerability to collapse.

Authors:
Babaei,K., Hawkins,N. M.

Keywords:
bridge and construction, bridge, earthquake, retrofitting, superstructure, prioritizing, costs

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Abstract:
Bridge expansion joints pose a special problem in the Washington State Department of Transportation (WSDOT) bridge deck management system. These devices are subject to repeated heavy dynamic loading, and premature failure has occurred in many cases. It is WSDOT policy, as part of the Bridge Deck Management System, to make expansion joints watertight in order to reduce the potential of substructure corrosion induced by roadway deicing salts and other contaminants.Expansion joint seals play an important role in keeping expansion joints watertight. A relatively new material, Evazote 50, looks promising in its performance characteristics as an expansion joint seal. It is able to accommodate considerable joint movement, its durability and corrosion resistant properties are excellent, and it is resistant to absorption of oils and greases. The purpose of this experimental project is to gain knowledge about the material\'s effectiveness over time and to gain knowledge about field installation techniques. It was very beneficial to have the manufacturer\'s representative on the job during installation. This was required by special provision and is a practice that should be continued on future projects.In-place performance will determine acceptance of Evazote 50 for general use.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
absorption, bridge, bridge deck, bridge deck rehabilitation, corrosion, Deck, durability, effectiveness, expansion joints, experimental, in-place, ITS, Joints, management, management system, performance, policy, roadway, salt, transportation, Washington, Washington state, WSDOT

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Abstract:


Authors:
Babaei,K.

Keywords:
bridge and construction, bridge

Abstract:
The performance of an experimental installation of PlusRide ACP as a bridge deck overlay is summarized in this report. Visual inspections, friction tests, noise readings, and rut depth measurements were taken on both the PlusRide and a rubberized ACP control section. No evidence of better frictional properties, noise reduction or increased service life could be attributed to the PlusRide in comparison with the rubberized ACP control section.

Authors:
Allison,R. E.

Keywords:
asphalt, asphalt pavement, bridge, bridge deck, bridge deck overlay, control, Deck, experimental, friction, inspection, noise, noise reduction, overlay, pavement, performance, PlusRide, resistance, Rubberized, tests

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External Links: http://wsdot.wa.gov/Research/Reports/100/130.2.htm

Abstract:
The Washington State Department of Transportation will be conducting experimental field testing of several selected polymer concrete thin (1/4 inch) overlays over a ten-year period. The polymer concrete material is manufactured by private industry firms and installed on selected bridge decks under standard WSDOT construction contracts. Approximately 21 bridges will be involved in the experiment; eight of these are included in federal participating projects as experimental features.Washington State Department of Transportation will be conducting experimental field testing of several selected polymer concrete thin (1/4inch) overlays over a ten-year period. The polymer concrete material is manufactured by private industry and installed on selected bridge decks under standard WSDOT construction 21 bridges will be involved in the experiment; eight of these are included in federal participating projects as features. The polymer concrete thin overlays were applied to the decks of the River Bridge and the Yakima River Bridge under Contract No. 3 SR 90 and SR 82, Interchange to Terrace Heights. Both bridges are steel truss bridges located on SR 82 just outside Yakima, Washington. Both the epoxy overlay and the methacrylate overlays were versatile products apply under difficult traffic control conditions. Starting and stopping the various pours to accommodate opening and closing of lanes for traffic proved satisfactory. To the extent possible, work was performed at night when traffic was light. All three lanes were then opened to traffic in the early morning to accommodate peak traffic conditions.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge deck repairs, bridge decks, bridges, concrete, condition, construction, contracts, control, Deck, Epoxy, experimental, lanes, light, overlay, overlays, polymer, polymer concrete, steel, steel truss bridge, thin overlay, traffic, traffic control, transportation, Washington, Washington state, WSDOT

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Abstract:
Washington State has approximately 700 bridge decks that may require a latex modified concrete (LMC) overlay in the next 12 to 15 years. The microsilica concrete overlay is seen as a possible alternative to the increasingly expensive latex modified concrete.A microsilica modified concrete overlay was placed on Bridge 5/718W in Skagit County.The bridge is a concrete box girder structure with 8,100 square feet of deck area. The ADT on this bridge is 9,150 vehicles per day.The minimum overlay thickness was 1% inches. Superplasticizer was added to the mix. The concrete was mixed in a conventional batch plant with the technical representative from the microsilica supplier providing assistance. The microsilica modified concreteoverlay was finished and cured as prescribed by WSDOTts specification for LMC overlays.The microsilica was supplied as a slurry. Force 10,000, produced by W. R. Grace and Company, Cambridge, Massachusetts, was the source of the microsilica.The long-term performance evaluation of the microsilica-modified concrete will be based on a direct comparison with the LMC overlay to be constructed on Bridge 5/71SE. Both bridges are of similar construction, have the same deck area and ADT, and have existing decks with similar levels of chloride contamination. Both overlays were constructed under the same contract.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
Alternative, bridge, bridge deck, bridge deck overlay, bridge deck repairs, bridge decks, bridges, chloride, concrete, concrete additives, construction, contamination, Deck, evaluation, latex modified concrete, microsilica concrete, overlay, overlays, performance, performance evaluation, silica fume, specification, Washington, Washington state

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Abstract:
Many anchorage systems of bridge expansion joints in the medium movement range have failed within a relatively short period of time after their installation. The embedded anchor devices have become loose under traffic impact and have caused deterioration of the adjacent concrete deck. After the performance of various domestic and foreign designs were assessed, factors affecting the anchorage system performance and failure were identified. Accordingly, improvements in the anchorage system components, which are built in conjunction with the anchor devices, were recommended to reduce the intensity of traffic impact loads transmitted to the anchor devices. Subsequently, an analytical procedure was developed to quantify the intensity of the dynamic traffic loads transmitted to anchor devices and to design anchor devices to resist those loads.

Authors:
Babaei,K., Hawkins,N. M.

Keywords:
bridge and construction, bridge, expansion joints, anchorage, concrete

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Abstract:
In this study a survey was conducted to ascertain the needs of employees of local governmental agencies with regard to the conduct of the design of bridges. Recommendations, relative to the development of standard plans which can be used by county engineers, are put forth. These recommendations are based on the needs of the local agencies, information regarding existing manufacturing capabilities, information concerning existing standard plans relative to bridges and information on an existing computer software program (BRADD-2) which is available from the AASHTO. The information on which the recommendations were made was obtained by telephone conversations, written questionnaires and/or personal visits with/form/to 75 local agencies (46 cities and 39 counties) in the state of Washington and by personal visits to 4 precasitng plants and 1 fabricating plant.

Authors:
Sorensen,H.

Keywords:
agencies, bridge, bridge design, bridge standards, bridges, computer, concrete, counties, design, development, fabricators, local government, precast, prestressed, program, software, standard plans, suppliers, survey, Washington

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Abstract:


Authors:
Sorensen,H.

Keywords:
bridge and construction, bridge

Abstract:
This Post Construction Report provides an overview of the selection of a chemical sealer and its use as a method of protecting the girders and piles of the Nasell River Bridge from the intrusion of chloride ions. The structure treated is located in a marine environment. Chem-Trete Silane sealer was used for this structure and applied as specified by the manufacture. After 1 1/2 years exposure to a salt environment no deteriation of the concrete has been detected. Monitoring of the structure will continue under Washinton State Department of Transportation\'s Bridge Inspection program.

Authors:
Toney,C. A.

Keywords:
bridge, chloride, concrete, concrete sealer, construction, corrosion, deterioration, environment, exposure, inspection, ITS, marine, monitoring, piles, program, salt, seal coat waterproofing, sealer, transportation

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Abstract:
A survey of standards for bridges, which exist in the U.S., was conducted, pertinent information concerning these standards was placed into a matrix spread sheet format using Lotus 1-2-3 and an IBM/PC. This information was reviewed for possible use in developing plans .for standard bridge systems, which could be used by county engineers in Washington.Information on types of standard bridge systems to be developed was obtained from Washington county engineers via a questionnaire. It is recommended that designs for at least one standard bridge system be developed for each of the primary materials readily available in Washington, namely: steel, concrete and wood. Other details, which should be included in the standards, are given.

Authors:
Sorensen,H., Olson,C. D.

Keywords:
bridge, bridge standards, bridges, concrete, counties, design, lotus 1-2-3, materials, microcomputer, spread sheet, steel, survey, systems, Washington, Washington County Engineers

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Abstract:
The Washington State Department of Transportation will be conducting experimental field testing of several selected ploymer concrete thin overlays over a ten-year period. The ploymer concrete material is manufactured by private industry firms and installed on selected bridge decks under standard WSDOT construction contracts. Approximately 14 bridges will be involved in the experiment.The study was conducted in cooperation with the U.S. Department of Transportation, Federal Highway Administration. The Washington State Department of Transportation will be conducting field testing of several selected concrete thin overlays over a ten-year period. The polymer concrete material is manufactured by private industry and installed on selected bridge decks under standard WSDOT construction contracts. 14 bridges will be involved in the experiment. The Snake River Bridge at Clarkston, Washington, Bridge No. 12/915, is the first bridge of the to receive a 1/4 thin overlay. The polymer concrete used is by Polycarb. The deck was repaired and overlaid in June of 1986. Work on the thin overlay began on June 8 and was completed on June 20. A total of 6,477 S.Y. of overlay was involved. Traffic was accommodated at all times on the portion of the bridge not being overlaid. Construction progressed relatively smoothly per the inspector\'s report. The material permitted the contractor flexibility in the rate of installation and in starting and stopping the work. Width of installation was varied to accommodate temporary traffic lanes. Pavement skid tests and bond tests all proved satisfactory. Ninety-one percent of the resistivity tests exceeded the minimum required by the specifications. The majority of the test points that did not meet the minimum specified occurred at the beginning of the work, where the contractor attempted to apply the material with spray that apparently did not provide accurate proportionate mix of the epoxy components. Subsequent tests and reports delamination, half-cell, chloride content, and rutting values to the original deck survey values.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge deck repairs, bridge decks, bridges, chloride, concrete, construction, contracts, Epoxy, experimental, half-cell, highway, lanes, overlay, overlays, pavement, polymer, polymer concrete, specification, specifications, survey, tests, thin overlay, traffic, transportation, Washington, Washington state, WSDOT

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Abstract:
The Washington State Department of Transportation will be conducting experimental field testing of several selected polymer concrete thin (1 1/4 inch) overlays over a ten-year period. The ploymer concrete material is manufactured by private industry firms and installed on selected bridge decks under standard WSDOT construction contracts. Approximately 21 bridges will be involved in the experiment; eight of these are included in federal participating projects as experimental features.The Grays River Bridge at Roseburg, Washington, Bridge is the second bridge of the federal aid projects to receive a thin concrete overlay. The polymer concrete used was Degadur 330, made by Degussa Company and installed by Floor. The deck was overlaid in August of 1986. Work on the thin overlay began on August 4, 1986 and was completed on August 5, 1986. A total of 586 S.Y. of overlay was placed. There was no traffic on the bridge during the overlay placement. The overlay contractor had a well trained crew and the overlay placement went very smoothly. The experience showed when the different operations of primer, overlay, and sealer were sequenced so that when one layer cured out, the next operation was ready to go. Friction tests and electrical resistivity tests were all satisfactory.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge deck repairs, bridge decks, bridges, concrete, construction, contracts, experimental, friction, overlay, overlays, polymer, polymer concrete, sealer, tests, thin overlay, traffic, transportation, Washington, Washington state, WSDOT

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Abstract:
This is the final report of PlusRide being used as the wearing course on a bridge deck overlay.A Class D Asphalt Concrete pavement which is an open graded friction course was used on an adjacent bridge as a control for the PlusRide. The PlusRide claims were high friction resistance, reduced noise, increased fatigue properties and deicing characteristics. The PlusRide cost 50 percent more that the Class D and the friction resistance, noise levels and fatigue properties were the same for the PlusRide and Class D. The deicing characteristics could not be confirmed due to the absence of surface icing on highways in the Yakima area.

Authors:
Peters,A. J., Schultz,R. L.

Keywords:
asphalt, asphalt concrete, Asphalt Concrete pavement, asphalt pavement, bridge, bridge deck, bridge deck overlay, claims, Class D, concrete, control, cost, Deck, fatigue, friction, highway, Highways, noise, overlay, pavement, PlusRide, resistance

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Abstract:
This is the post construction and one year evaluation Report of being used as the wearing course on a bridge deck overlay under very high traffic volumes. A rubberized Class D Asphalt Concrete Pavement friction course was used on an adjacent bridge to compare against the PlusRide. The properties evaluated were friction resistance, noise, fatigue properties and deicing characteristics. The friction and noise properties are the same. The PlusRide has deeper ruts and large areas in the traveled lane have delaminated. The deicing characteristics have not been confirmed. The rubberized class ACP is performing better than the PlusRide.

Authors:
Peters,A. J., Schultz,R. L.

Keywords:
asphalt, asphalt concrete, Asphalt Concrete pavement, asphalt pavement, bridge, bridge deck, bridge deck overlay, bridges, Class D, concrete, construction, Deck, evaluation, fatigue, friction, friction course, noise, overlay, pavement, PlusRide, resistance, Rubberized, traffic, traffic volumes, volume

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Abstract:
This study investigated the feasibility of eliminating endblocks from pretensioned continuos bridge girders. The removal of endblocks is estimated to reduce girder costs by 5 to 10 percent. The girders studied were the Washington State Department of Transportation\'s \"Series 14\". These girders are characterized by 5 inch thick webs and are prestressed with both harped and straight 1/2 inch diameter grade 270 stands. Previous research had recommended the elimination of endblocks for simple span bridges. This study dealt with continuous bridges.The research consisted test and a destructive laboratory test. The field test was used identify bases for the destructive testing. \"Series14 \" girder with endblocks and \"Series 60\" girders without endblocks were instrumented with strain gages and monitored from the time they manufactured to the time thel oads were tested on the bridge. The laboratory test was performed with a balanced cantilever arrangement using two \"14\" girders without without endblocks. The joint at the support was made continuous by providing deck reinforcement in a manner similar to reinforcing details used by WSDOT. Concentrated incrementally applied at a distance of 13 ft.10 inches from the continuous support. The modified girders performed effectively under applied loads. Therefore, endblocks may be removedfrom continuous Series \"14\" girders with normal diaphragms. The study recommends that one \"Series 14\" continuous girder without endblocks be designed and monitored through the various stages ofconstruction and service in another bridge.

Authors:
Itani,R., Hiremath,G. S., Vasisth,U.

Keywords:
base, bridge, bridges, concrete, construction, cost, costs, Deck, design, diaphragms, endblocks, field test, girders, loads, prestressed, prestressed concrete, Prestressing, pretensioned, reinforcement, research, span, transportation, Washington, Washington state, WSDOT

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Abstract:
This report is designed to provide information to guide inspectors of wood highway structures in the use of stress wave inspection technology. It explains the methods and instruments used to measure the velocity of stress waves (sound) in wood. The characteristic behavior of sound waves in wood of various species, moisture content, preservative treatment and infection by wood destroying organisms is described. The important effects of the anatomy of wood and the orientation of grain and annual rings to the wave path are discussed to aid in the interpretation of measurements. Characteristics of the instrumentation essential to its calibration are explained and instruction is provided in the appropriate use of these tools. This report has been written to serve as a manual for \"on site \" stress wave inspection of the kind of wood structures found in highway systems. It is a compendium or experience in the field inspection of many wood buildings and highway bridges. Original research conducted to fill in voids in the published studies, is described in the Appendices.

Authors:
Hoyle,R. J. Jr, Rutherford,G. S.

Keywords:
behavior, bridge, bridges, calibration, grain, highway, insect damage, inspection, ITS, manual, nondestructive testing, research, sound waves, Stress waves, stresses, structures, systems, technology, termite damage, velocity, wood decay

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Abstract:
Darex Corrosion Inhibitor (DCI) was specified for use in the Dogfish Bay Bridge on SR 308 in Kitsap County. The bridge is a 90-foot long structure located within a tidal zone. The superstructure is an 18-inch deep prestressed concrete slab. Darex Corrosion Inhibitor (DCI) was specified for use in the Dogfish Bay Bridge on SR 308 in County. The bridge is a 90-foot long structure located within a tidal zone. The superstructure is an 18-inch deep prestressed concrete slab. The end piers and two intermediate piers each consist of six 16%-inch prestressed concrete piles. DCI was added to all concrete used in the slab and piles except for four control piles (one in each pier). The supplier, Grace Construction Products, claims that the Calcium Nitrite contained in DCI will, when used as an additive in the recommended dosage, strengthen the passivating film around the reinforcing steel \"making it more resistant to chloride penetration,\" thereby protecting the steel against corrosion. (The process is explained in detail in Appendix A. ) However, only half of the recommended amount of DCI was added to the test sections. At this dosage, DCI appears to be no more effective than standard Portland Cement Concrete in preventing corrosion of the reinforcing steel.

Authors:
Henley,E. H. Jr

Keywords:
additive, bridge, bridges substructure, calcium nitrite, chloride, claims, concrete, construction, control, corrosion, counties, Darex Corrosion Inhibitor, DCI: calcium nitrite, deterioration, effectiveness, piers, piles, portland cement concrete, prestressed, prestressed concrete, reinforcing steel, steel, superstructure

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Abstract:
The Washington State Department of Transportation (WSDOT) designed and installed Service Level 1 (SL-1) bridge rails on three treated timber bridges in the state. To date there have been no accidents or maintenance problems reported at any of the modified bridges.

Authors:
Gripne,D.

Keywords:
accidents, bridge, Bridge rail modification, bridges, maintenance, Rail for Timber Bridge, systems, traffic, transportation, Washington, Washington state, WSDOT

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Abstract:


Authors:
Babaei,K., Hawkins,N. M.

Keywords:
bridge and construction, bridge deck, concrete, evaluation, bridge

Abstract:
This report describes the installation and post-construction evaluation of a thin, lightweight epoxy concrete bridge deck overlay. This subject "Flexolith" epoxy concrete system was installed by Dural International Corporation on a bridge located on I-82 near Ellensburg, Washington.The application of the overlay was unique in both the use of a special machine which mixed the epoxy components with the aggregates and the use of a vibratory screed to distribute and level the epoxy concrete to the desired depth. A small segment of the overlay, however, was placed using the more common broom and seed method of installation.Post-construction testing showed that the overlay has adequate bond strength, extremely high friction resistance and is performing adequately as a waterproof membrane. The only deficiencies noted were a nonuniform surface texture and profile. A recommendation was made to not allow the use of the vibratory screed method until improvements are made to insure that the final product will have a surface texture and profile equivalent to overlays placed with the broom and seed method.

Authors:
Anderson,K. W.

Keywords:
aggregate, bridge, bridge deck, bridge deck overlay, bridge decks, concrete, concrete bridge, construction, Epoxy, evaluation, lightweight, membrane, overlay, overlays, profile, resistance, strength, Washington

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Abstract:
The cathodic protection on the 522 interchange near Woodinville, Washington was evaluated for proper operation. Three of the five zones on the bridge appeared to be cathodically protected. The current was increased in one of the unprotected zones to provide protection. The zone could not be fixed due to the nonfunctional nature of thermistors, reference electrode and structure cables. A recommendation was made to deactivate the entire system for a period of two weeks to allow for depolarization. Following depolarization, native state potential valves should be measured to establish a basis of comparison before activating the system. Monitoring on a three month interval for one year should be done to ensure that all problems have been solved.

Authors:
Telford,E. R., ETCO Engineering Services,Inc

Keywords:
bridge, cathodic protection, corrosion, monitoring, protection, System, Washington

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Abstract:
The cathodic protection system on the Yakima River Bridge on SR-24 near Yakima was evaluated for proper operation. Three out of six reference electrodes and rebar probes were found to be non-functioning. One temperature sensing thermistor was also found to be non-functional. All three deck zones were found to be receiving the proper cathodic protection current. Recommendations were made to continue the monitoring at regular intervals and maintain the present rectifier settings.

Authors:
Telford,E. R., ETCO Engineering Services,Inc

Keywords:
bridge, cathodic protection, Deck, monitoring, probe, protection, System, temperature

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Abstract:
Under FHWA Demonstration Project No. 34, \"Cathodic Protection for Reinforced Concrete Bridge Decks,\" a slotted cathodic protection system was installed on the ES ramp in the Woodinville Interchange during the summer of 1985. The slotted cathodic protection system involves sawing by slots longitudinally in the existing deck at one-foot centers. Platinum wire or carbon strand wire is placed in the cut slots first and then conductive polymer is filled in the slots. Electric power from a rectifier supplies current to the wire and conductive polymer. The current then flows to the top mat reinforcing steel, giving the steel protection from further corrosion. The objective of the demonstration project was to familiarize the Washington State DOT with this new technology. This objective was fulfilled. Some problem areas with the system were identified during the work:1.A more positive method of finding grounding locations from the anode to nicks, ties, etc. needs to be developed. Perhaps an instrument can be used to supplement visual inspection. 2.The necessity for having a minimum of 112-inch cover from the bottom of the slot to the top of the needs to be resolved. 3.A better method of installing the conductive polymer needs to be developed. Hand spreading of the material from plastic bags results in sloppy work. 4.Procurement time for the rectifier needs to be shortened. 5.The project, once it has started, moves along very rapidly, there is very little time for on-the-job training of workers. Workmen should have prior experience at this work. In remote areas, sources of electrical power may not be available. It will be necessary for sources of power, such as solar panels or long-lasting batteries to be developed for this system.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge decks, cathodic protection, concrete, concrete bridge, construction, corrosion, Deck, developed, flow, inspection, plastic, polymer, project, protection, reinforced concrete, reinforced concrete bridge, reinforcing, reinforcing steel, steel, steel protection, supply, System, technology, training, Washington, Washington state

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Abstract:
Under FHWA Demonstration Project No. 34, \"Cathodic Protection for Reinforced Concrete Decks,\" a non-slotted cathodic protection system was installed on the deck of the Yakima Bridge near Yakima, Washington, in the summer of 1985. The project involved repairing deck, then fastening Raychem pre-manufactured anodes to the deck to impress current to the mat rebar. Impressing current through the concrete to the top mat steel prevents corrosion of the steel. A latex modified concrete overlay was placed over the deck anode. The objective of the demonstration project to familiarize the Washington State DOT with new technology. This objective was fulfilled. Some problem areas with the system were identified during the work: 1.A more positive method of finding electrical grounding locations from the anode to nicks, ties, etc., needs to be developed. Some ties were exposed during the scarifying operation Perhaps an instrument can be used to supplement visual inspection. 2. An effective technique of allowing concrete trucks to drive on the anode without damaging needs to be developed. 3.An effective method needs to be developed to locate breaks in the anode as well as shorts. 4. In remote areas, sources of electrical power may not be available. It will be necessary sources of power, such as solar panels or long-lasting batteries to be developed for this system. 5. Since the project, once it has started, moves along very rapidly, there is very little time on-the-job training of workers. Workmen should have prior experience at this work. These problems need to be overcome to obtain a better quality product.

Authors:
Roper,T. H., Henley,E. H. Jr

Keywords:
bridge, bridge deck, bridge decks, cathodic protection, concrete, concrete bridge, construction, corrosion, Deck, developed, inspection, latex modified concrete, overlay, project, protection, quality, reinforced concrete, reinforced concrete bridge, steel, System, technology, training, truck, trucks, Washington, Washington state

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Abstract:
An extensive state-of-the-art review of construction methods and results for latex modified concrete (LMC) and low slump, dense concrete (LSDC) overlays is presented in this report. Recommendations are made for improvements in construction procedures, inspection, and specifications. An analysis and preventative measures for plastic shrinkage cracks in LMC are presented. Other alternate bridge deck protective systems were examined.

Authors:
LaFraugh,R. W., Zinserling,M. H.

Keywords:
analysis, bridge, bridge deck, bridges, concrete, concrete overlays, construction, construction methods, cracking, Deck, improvement, inspection, Interim, latex modified concrete, low slump dense concrete, methods, overlay, overlays, plastic, review, shrinkage, specification, specifications, state-of-the-art, System, systems

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Abstract:
The pavement management system developed by the State of Washington was modified to meet the needs of the counties in the State of Washington within the constraints of available data and resources. The modified system, called the Washington County Pavement Management System (WCPMS), was tested for Thurston and Benton counties. Results of this testing show that; (1) The WCPMS can be operated using the existing data in the county road log in combination with collected pavement condition survey data; (2) computer resources are available to most counties to access the State computer to execute the various programs in the WCPMS; and (3) routine usage of the WCPMS for a network of 1000 miles will require a level of effort of about 150 person-days and a computer cost of $1,000.

Authors:
Kramer,S. L., Sivaneswaran,N., Tucker,K., Kulkarni,R. B., Finn,F. N.

Keywords:
bridge, design, hinge, earthquake, evaluation restrainers, pavement management, pavement management systems, counties

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Abstract:


Authors:
Hallenbeck,M. E., Hooks,J.

Keywords:
transport, weight, weigh-in-motion, bridge

Abstract:
This study was conducted to determine the wear characteristics of bridge decks overlayed with Class D (open-graded) asphalt concrete. A total of 74 bridges were inspected and rated during the period May to August, 1984.This study was conducted to determine the wear characteristics of bridge decks overlayed with Class (open-graded) asphalt concrete. A total of 74 bridges were inspected and rated during the period May to August, 1984. A rating system was developed to allow a numerical comparison between bridges, and also to establish levels of tolerable differences. Values for a variety of problem areas were assigned in ascending order according to severity. Refer to page 10 for deficiency rating values, To use the system the bridge deck is inspected and values assigned according to visual observations. For example, if a bridge deck had some raveling, severe rutting and a transverse crack at the expansion joint, a rating of 5 (some raveling) 6 (severe rutting) + 2 (traverse expansion joint crack) = 13 would be applied. To further clarify the rating system used on page 4 through under the column headed \"Class of Defects\", the following examples are used. 1. On page 4, Bridge No. E had a rating of The rating total would be = 10, which is in the column headed \"Rating\". 2. On page 5, Bridge No. W had a rating of B-4. The rating total would be B (expansion dam failure) + 4 (some rutting). Since there is no numerical value for B the total is 4, which is listed in the column headed \"Rating\". After comparing ratings of all 74 bridges, three of serviceability were established, Categories A, and C, which are discussed in detail in the memo of August 13, 1984, on page 2 Photo Examples Rating 0-Category A -Bridge No. 90/59E-N -page 35 Rating 2 -Category A -Bridge No. -pages 51-52 Rating 6 -Category -Bridge No. -page 13 Rating 10 -Category B Bridge No. E -page 15 Rating 21 -Category C -Bridge No. N -pages 46-47

Authors:
Gietz,R. H.

Keywords:
asphalt, asphalt concrete, bridge, bridge deck, bridge deck overlay, bridge decks, bridges, Class D, concrete, Deck, overlay, overlays

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Abstract:


Authors:
Hawkins,N. M.

Keywords:
bridge and construction, bridge

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Abstract:
The Washington State Department of Transportation (WSDOT) designed and installed Service Level 1 (SL-1) bridge rails on three treated timber bridges in the state. To date there have been no accidents or maintenance problems reported at any of the modified bridges.

Authors:
Gripne,D.

Keywords:
accidents, bridge, Bridge rail modification, bridges, maintenance, Rail for Timber Bridge, systems, traffic, transportation, Washington, Washington state, WSDOT

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Abstract:


Authors:
Babaei,K., Terrel,R.

Keywords:
bridge and construction, bridge, water proofing, membrane, WSDOT

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Abstract:
The purpose of the study is to determine how distinctive social, economic, land use, governmental and political characteristics in the Vancouver-Portland area to uneven growth which in turn affects the transportation system. Interviews with public and private industrial representatives to identify the reasons underlying uneven growth are discussed. A statistical analysis of population, employment, vehicle registration and traffic across the Interstate 5 bridge connecting Vancouver and Portland is also presented. Recommendations are listed which suggest ways to improve the transportation system through modification of elements contributing to uneven growth.

Authors:
Public Transportation and Planning Division, Washington State Department of Transportation

Keywords:
analysis, bi-city, bi-state, bridge, economic development, employment, industrial location decision, interviews, land use, land use sewerage, land-use, population, public, statistical analysis, Study, System, traffic, traffic volumes, transportation, Uneven growth rate

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Abstract:


Authors:
Babaei,K.

Keywords:
bridge and construction, bridge

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Abstract:
The 1974-79 study of the maintenance problems of the drawspan mechanism of the Evergreen Point Bridge across Lake Washington is reported. The approach was to predict the life of elements by Miner's hypothesis. For this the strains at critical points and the wind vector were measured over two sessions. These results were correlated with long term wind data to provide the number of cycles in a year at various stress levels. The fatigue capacity of anchor rods was determined by the Prot test on six specimens. The resulting S-N curve compared to the field measurements to determine the expected life of the rods from the Miner criterion. The methods developed provide useable maintenance procedures for the prevention of fatigue failure of critical structural elements.

Authors:
Brown,C. B.

Keywords:
bridge, data, developed, fatigue, maintenance, methods, reliability, strains, stresses, Washington, wind

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Abstract:
This report includes a full year of field data and a synthesis of all data. These include 422 hourly events of which 351 occurred in the 1977-78 season. This use of Miner's hypothesis is justified in this report.

Authors:
Brown,C. B.

Keywords:
Annual, bridge, data, fatigue, maintenance, reliability, season, wind

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Abstract:
This report reflects a year of calms with little addition to the data base. Pressure transducers were placed and an analytical scheme is reported. This scheme was subsequently used in the final work.

Authors:
Brown,C. B.

Keywords:
Annual, base, bridge, data, fatigue, maintenance, pressure, reliability, wind

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Abstract:
This report reflects a year of data gathering together with the completion of analysis programs. These include the initial tape conversion, data rejection and selection, fast Fourier transform coefficient computation. Complete statistics of measurements are given.

Authors:
Brown,C.

Keywords:
analysis, Annual, bridge, data, fatigue, maintenance, program, reliability, statistics, wind

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Abstract:
Forty-eight bridge decks were investigated for deterioration using visual , mechanical , electrical and chemical techniques. Data from the various techniques and the techniques themselves were compared and evaluated, resulting data base for Washington's bridges and recommendations for efficient condition determinations. Of the thirty-seven bridges for which all four types of inspection could be accomplished, twenty-nine were deteriorating as evidenced by delaminated concrete, and only two had non-deteriorating scores for all four techniques. None of the investigative techniques used in the project have been shown able to predict deck deterioration problems six to eight years in advance, our desired time period for project planning. The mechanical technique, commonly referred to as the "chain drag", is the method recommended for continued use by bridge inspection crews. Forty-eight bridge decks were investigated for deterioration using visual, mechanical, electrical and chemical techniques.

Authors:
Demich,G. F.

Keywords:
base, bridge, bridge deck, bridge decks, bridges, Chloride ion, delamination, half-cell potential, de-icing salt, Galvaic corrosion, concrete cover, bridge deck deterioration, concrete, condition, data, deck, deterioration, inspection, planning, Washington

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Abstract:
This report completely describes the instrumentation on the drawspan of this Evergreen Point Bridge. The design and construction of the data recording system, with the complete calibration of the measurement and collection system is given. Initial data collection and preliminary analysis is set out. The analysis was subsequently abandoned, the data was retained.

Authors:
Brown,C. B.

Keywords:
analysis, Annual, bridge, calibration, construction, data, data collection, design, fatigue, maintenance, reliability, System, wind

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Abstract:
The porous walled resonating chamber, a type of breakwater, is investigated as a means of reducing reflected waves from structures subjected to random wind generated waves in deep water. Extending laboratory monochromatic studies to a full-scale apparatus appended to a floating bridge allows assessment of scale factors and the effects of random waves on the predicted performance of thedevice as a linear damped oscillator . The full-scale device is shown to be frequency selective at a frequency precisely corresponding to the predicted resonance of the system. The forces, measured on the porous wall, are lower than predicted and the device completely eliminates the problem of wave runuponto the bridge roadway. The method of evaluating the energy attenuation by the breakwater incorporates spectral analysis of digitized data recorded at fixed locations equidistant in front of the chamber and at a remote station away from the influence of the breakwater. Analysis demonstrates that the time average energy density at a fixed location where incident and reflected waves co-exist is influenced not only by the wave amplitudes, as expected, but also by the product of the amplitudes and a function of the phase angle. The chamber effects a change in the random phase angle during reflection , producing a different effective distance of wave travel to the fixed location and thus negating quantitative analysis of the energy dissipation.

Authors:
Richey,E. P., Morden,D. B., Hartz,B. J.

Keywords:
analysis, Assessment, attenuation, Breakwater, bridge, data, density, Energy, floating bridge, forces, incident, performance, roadway, structures, travel, Wave attenuation, wind

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Abstract:
A study was conducted on the character and significance of highway runoff waters for the Washington Department of Highways and the Federal Highway Administration. This preliminary appraisal of runoff quality consisted of a literature review and critique plus a limited amount of field sampling on SR 520. Although a large amount of information is present in the literature concerning urban run off, there is very little strictly related to highways and their rights-of- way. Highway runoff is similar t o urban area runoff but may be higher in heavy metals and oil. A significant fraction of the heavy m e t an l s, oil and nutrients are adsorbed to the dust and dirt fractions and then may be removed by sedimentation. Runoff from the lake bridges should have a very insignificant effect on Lake Washington in comparison with the urban run off to the Lake. Recommendations are made for mitigating runoff effects and for conducting an intensive study of highway run off water quality and its significance.

Authors:
Sylvester,Robert O., DeWalle,Foppe B.

Keywords:
bridge, bridges, environment, heavy metals, highway, highway runoff, Highways, ITS, metals, quality, review, runoff, sampling, sedimentation, Study, urban, vehicle emissions, Washington, water quality

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Abstract:
At the request of the Washington Department of Highways a comprehensive study was conducted of the exposures of toll collectors to carbon monoxide at the Evergreen Point Bridge spanning Lake Washington between Seattle and Bellevue.The first phase of the study consisted of designing, installing and operating an automatic, continuous carbon monoxide monitoring system to establish typical air quality patterns in and around the toll booths.the second phase consisted of developing a prototype toll booth positive ventilation system. Air, which is introduced through a vertical diffuser situated at one wall of the booth, travels horizontally across the booth and out the door. Parametric studies of sources and rates of ventilation air, diffuser design and other toll booth modifications were conducted in the laboratory. Subsequently these modifications were installed and investigated at an operating booth at the toll plaza. Concentrations of carbon monoxide in the collectors breathing zone were reduced to acceptable levels. Methodologies and results of these systems are described, and design recommendations for the control system are offered.

Authors:
Rossana,T. A., Hall,F. A.

Keywords:
air quality, bridge, carbon monoxide, Concentrations, control, design, exposure, highway, Highways, methodology, monitoring, Operating, quality, seattle, System, systems, travel, Washington

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Abstract:
The purpose of this study was to investigate the acoustic effects of two topping materials used on bridges in the Seattle area. One material was applied to the bridge on Interstate-5 which crosses the Duwamish River. It is an English product called Sprag-Grip which is supposed to have very good anti-skid properties, as well as the ability to stick to the road in thin layers thus making it suitable for the repair of worn surfaces. The other material is an epoxy -asphalt mixture which was applied to some sections of the Evergreen Point Floating Bridge over Lake Washington, particularly over sections where worn grating was causing excessive noise. Hopefully, this substance will be capable of long-term sticking in relatively thin layers. Of the two materials, it was found that the epoxy-asphalt topping on the Evergreen Point Floating Bridge was by far the quieter, and, at least as newly applied, proved to be very quiet at the road/tire interface. It is likely that this good acoustic performance is due to the smoothness of the surface rather than directly to the fact that the material contains epoxy. The role of the epoxy would be as an adhesive and to resist wear so that its original acoustic performance could be maintained for a considerable length of time. Spray-Grip, on the other hand, although slightly quieter than the rutted, worn roadway, was not as quiet as the original unworn road surface. Experimental Procedures The primary contribution of a road surface to the noise 'radiating from a vehicle is in the noise emitted at the road/tire interface; therefore, the major thrust of this effort was directed toward measuring this effect. There also were some measurements of community noise levels before and after the resurfacing of the bridges. The tire noise tests were taken on the right rear wheel of a Laboratory station wagon upon which a new tire was mounted (a Pennsylvania Patrol Special, size 8. 55-15). (The tread design and depth of this tire are shown on page 2. ) This tire was mounted on a wheel and used on the vehicle only daring tests. Between tests it was stored so that unnecessary wear would not change its acoustic character-teristics. The noise pickup device was a specially baffled microphone located about 7 inches from the road/tire interface by a bracket holding it on the outside of the tire. One of the major problems in making noise measurements of this type is to have a microphone that will pick up only tire noise and be baffled from wind noise. This problem has been solved by a microphone baffling system especially designed by this Laboratory.

Authors:
Foss,Rene N.

Keywords:
asphalt, bridge, bridges, community noise, design, Epoxy, experimental, floating bridge, highway, ITS, materials, mixture, noise, Noise Levels, noise measurements, performance, repair, roadway, seattle, Study, System, tests, tire, tire noise, Washington, wind, Wind Noise

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Abstract:
At the request of the Washington Department of Highways two studies have been conducted by a team of specialists at the University of Washington Air Resources Program to determine the applicability of the Acoustic Radar to air quality modeling to mobile sources.At the request of the Washington Department of Highways two studies have been conducted by a team of specialists at the University of Washington Air Resources Program to determine the applicability of the Acoustic Radar to air quality modeling of mobile sources. Following an exploratory investigation, a comprehensive study was undertaken in which the atmospheric structure was measured by a modified Monostatic Acoustic Radar and the derived stability conditions were compared with the commonly used Pasquill-Turner stability classes, which are based on empirical data. This comprehensive study was performed over a three month period in the fall of 1976, when an unusually persistent air stagnation existed in the study area caused by a stationary high pressure system over the entire Northwest.The Evergreen Point Floating Bridge Toll Plaza in Bellevue, Washington was selected for test location.The carbon monoxide (CO) concentrations were measured at six strategically located sampling points and then compared with the computer model predictions utilizing atmospheric stability data derived by both the Pasquill-Turner and the Radar echo methods. The results indicated that the Acoustic Radar method of determining D & E stability classes is a more realistic approach than that of the Pasquill-Turner Method. Furthermore, the Radar method can also provide continuous remote sensing and recordings of atmospheric parameters. The variation of the inversion height, as measured by the Radar echoes has shown a reasonably good correlation with the variation of the measured CO concentration.

Authors:
Rossano,A. T., Badgley,F. I., Juhasz,P. C., Bang,G., Carsey,F.

Keywords:
Acoustic Radar, air pollution, air quality, Air Quality Modeling, bridge, carbon monoxide, Carbon Monoxide Perdictions, computer, Concentrations, condition, data, floating bridge, highway, Highways, ITS, model, modeling, prediction, pressure, program, quality, remote sensing, Remote Sensing Atmospheric Structur, sampling, stability, Transportation Pollutio, Washington

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