Abstract:
This research was Phase III of field investigations carried out over 12 years at a test section in southwest Washington State in an effort to quantify the contribution of geotextile separators to the long-term performance of pavement sections. Five different geotextile separators, as well as a control (soil-only) section, were installed in a test section covering two lanes with different base course thicknesses on a low volume but heavily loaded rural highway west of Bucoda, Wash. Phase I evaluated the performance of the separators during construction. Phases II and III were conducted to evaluate the performance of the separators 5 and 12 years after construction, respectively. Field and laboratory tests were conducted on the subgrade, granular base materials, and the geotextiles as part of the effort to correlate the performance of the pavement section to the presence of the geotextile separators. Falling weight deflectometer (FWD) testing was also performed at the site as part of the effort to quantify the performance of the pavement section. The laboratory tests indicated that the geotextiles successfully performed their separation function over the 12-year period. However, the soil-only sections had a minimal amount of intermixing at the base course/subgrade interface, indicating that the separation benefits of geotextiles may not be realized under relatively thick pavement sections. Field density tests indicated that the density of the subgrade in the sections with a geotextile generally increased between construction and the first field investigation, whereas the density of the soil-only sections remained about the same. Similarly, the FWD tests showed that the most significant increase in the subgrade moduli occurred in the first few months following construction. However, the soil-only sections exhibited behavior similar to the sections with geotextiles during the FWD testing, suggesting that for the relatively thick pavement sections, incorporation of geotextiles may not have provided a significant contribution to the overall performance of the section over the 12-year period. Some of the FWD results did suggest that geotextiles might contribute to an increase in the base course modulus over time.

Authors:
Collins,B. M., Holtz,R. D.

Keywords:
base, behavior, benefit, benefits, construction, control, density, falling weight deflectometer, field investigations, geotextile, geotextile separators, highway, materials, moduli, pavement, pavement performance, pavement section, research, rural, separators, subgrade, tests, volume, Washington, Washington state, weight, performance

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/595.1.pdf http://wsdot.wa.gov/Research/Reports/500/595.1.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:
Funded by the 1987 Intermodal Surface Transportation Efficiency Act, the Strategic Highway Research Program (SHRP), was a five year, $150 million research program to improve the performance of the nation's roads by addressing four key areas: concrete and structures; highway safety and maintenance; asphalt; and long-term pavement performance. Nearly one-third of the $150 million was allocated for the study of asphalt, specifically to develop performance based specifications that would relate material properties of the binder and the mix to field performance. Superpave (Superior PERforming asphalt PAVEments) encompasses the products of the SHRP asphalt research program and consists of three interrelated elements: an asphalt binder specification with supporting tests; a mix design and analysis system with supporting tests; and performance prediction models. This report is a compilation and synthesis of Washington DOT's (WSDOT) experience with selected components and concepts of the SHRP/Superpave technology to include the following: performance graded (PG) binder usage and specification validation; gyratory mix design; the Superpave Shear Test (SST); and field performance of the Superpave mixes.Binders typically specified by WSDOT (AR400OW and PBAs -2, -5, -6. -6GR) were classified in terms of five Superpave performance grades: PG 58-22; 64-22; 64-28; 64-34; and 70-28. Although data from 171 weather stations suggest that as many as 6 low- and 5 high-temperature grades could be specified, binder availability and regional pavement distress were used to develop guidelines for statewide PG usage. Three binders were recommended for use in the western, northeastern and southeastern regions of the state as follows: PG 58-22; PG 58-34; and PG 64-28, respectively. Validation of the binder specification with respect to low temperature cracking was accomplished using binder and field performance data from 28 projects. The results were very encouraging: the original SHRP algorithm for binder selection correctly "predicted" field performance in 22 of 28 cases, whereas the LTPP algorithm for binder selection correctly "predicted" field performance in 26 of 28 cases.Additionally, a laboratory experiment using the Superpave Shear Test (SST) apparatus was undertaken to test the effectiveness of binder "bumping," i.e., increasing the high temperature grade because of exceptionally high traffic volume and/or slow or standing traffic. The data clearly indicate that the SST is an effective tool for discriminating between binders and that 'bumping" may be effective in reducing pavement rutting. Permanent shear strain for specimens made with a PB 70-xx binder was only 25 to 33% of the shear strain for specimens made with a PG 58-xx binder.As originally configured, the Superpave mix design matrix included seven traffic levels and four temperature regimes for 28 possible compaction levels. Recognizing that the 28 compaction levels made for a somewhat unwieldy system, WSDOT attempted to reduce the number of compaction levels by conducting a series of mix designs at each compaction level. The results of the limited experiment suggest that it might be possible to limit the number of compaction levels required for mix design. Research by Brown et. al. (NCHRP 99) tends to confirm this as they have suggested reducing the number of compaction levels and provided more definitive guidance with respect to each level.Since 1993 WSDOT has place 44 projects which include some component of the Superp ave technology. For 17 of these projects parallel Hveem and Superpave mix designs were conducted. In 13 of the 17 cases, the Superpave design asphalt content was equal to or greater than the Hveem design asphalt content, though the difference was usually no more than 0.2%. A fundamental difference between Hveem and Superpave mix design methods is the compaction device. Data from these field projects indicate that the current kneading and gyratory compaction protocols (at least for 109 gyrations) yield similar air void contents.As noted previously, Washington DOT has placed 44 projects which involve some component of the Superpave technology. For 18 of the projects a conventional Hveem mix design was conducted using a PG binder (Hveem-PG). The remaining 26 projects were truly Superpave, i.e., the materials selection and mix design were established in accordance with the Asphalt Institute's SP2, Superpave Level 1 Mix Design. According to WSDOT practice the following numerical indices trigger maintenance: Pavement Structural Condition (PSC) 10 mm; or International Roughness Index (IRI) > 500 cnVkm. Although relatively "young", the 44 projects are performing quite well. The average values of rutting, PSC, and IRI (4, 91, and 121, respectively) are all well below the "trigger" values. With respect to rutting and PSC, the performance of Hveem-PG and Superpave projects is virtually identical. However, the ride quality of the Superpave projects is a bit rougher than the Hveem-PG binder projects: IRI of 134 for the former and 103 for the latter. The higher values of IRI measured on the Superpave projects may be the result of the typically coarser aggregate gradation or differences in construction techniques.WSDOT's Superpave experience has not been without challenges. Still, its overall experience has been very encouraging. Experimentation with the revised compaction matrix, continued use of the SST, field validation of the "bumping" experiment, and long-term monitoring of field performance will provide the necessary data to allow WSDOTs critical assessment of Superpave's technical merit and economic viability.

Authors:
Leahy,R. B., Briggs,R. N.

Keywords:
SHRP, Superpave, asphalt, intermodal, transportation, transportation efficiency, highway, research, program, performance, concrete, structures, highway safety, safety, maintenance, pavement, specifications, specification, asphalt pavement, pavements, tests, design, analysis, prediction, models, Washington, WSDOT, data, temperature, cracking, LTPP, traffic, volume, compaction, materials, condition, international roughness index, roughness, index, ride quality, quality, aggregate, construction, ITS, monitoring

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Abstract:
The Seattle Wide-area Information for Travelers (SWIFT) project was a highly successful Intelligent Transportation System (ITS) Field Operational Test (FOT) that was conducted over a four-year period from 1993 to 1997. The purpose of the project was to test the efficacy of a High Speed Data System (HSDS), or FM Sub-carrier, to disseminate incident, bus and speed congestion information via three different end-user devices: pager watch, portable computer and in-vehicle navigation device. Six hundred ninety (690) commuters, many with route- or mode-choice options, participated in the FOT and provided user-acceptance evaluations. Other evaluation components examined the system architecture, communications coverage, deployment cost and institutional issues that affected the project.The primary purpose of the SWIFT Institutional Issues Study evaluation was to collect information regarding the institutional issues (e.g., policies, jurisdictional issues, internal and external factors) that affected design, development, testing, deployment and conduct of the SWIFT Field Operational Test (FOT); determine how these issues were overcome and what lessons could be learned. A secondary purpose of the evaluation was to document the history of the SWIFT project.The methodology for the SWIFT Institutional Issues Study consisted of two sets of questionnairesand two sets of semi-structured interviews that were conducted with fourteen (14) SWIFT team memberrepresentatives at two different points during the conduct of the SWIFT FOT: about midway through the conduct of the test and after the test was completed. All SWIFT team member responses were independently collected and SWIFT institutional issues were primarily identified by determining which topics were addressed by two or more individuals. Historical information was collected from various sources throughout the project.SWIFT represents one of the first ATIS FOTs conducted in this country. Earlier tests were conducted in Orlando, FL (TravTek) and Minneapolis St. Paul (Genesis) among others, yet the SWIFT FOT appears to have extended considerably the available database of information regarding ATIS effectiveness and acceptance. The addition of real-time bus information, in particular, has set the SWIFT FOT apart from others already conducted.One of the significant aspects of the SWIFT teaming agreement was the long-term interest in ITS and commitment of the organizations involved. For instance, the majority of the SWIFT team members articulated a long-term interest in ITS deployments. In addition, three organizations-Seiko, Etak and Metro Traffic Control-+ommitted themselves to fielding a \"SWIFT-like\" system after the project was completed. This degree of interest and commitment resulted in all of the SWIFT team members working together in a very effective, cooperative fashion throughout the FOT.A critical organizational structure that was instituted to implement SWIFT was the weeklyteleconference. This simple, yet cost-effective method of managing and discussing the technicalissues involved with the project was attributed by many of the SWIFT team members to aprimary instrument of the project\'s success. In particular, the SWIFT teleconferences enabledthe representatives of each organization to keep abreast of the developmental status of theproject, to brainstorm solutions to encountered problems and to develop scheduling sense.

Authors:
Wetherby,B.

Keywords:
ATIS, bus, computer, congestion, congestion information, cost, data, database, design, development, effectiveness, evaluation, incident, Institutional, Intelligent transportation system, interviews, Issues, ITS, methodology, mode choice, policy, portable computer, project, scheduling, seattle, speed, SWIFT, System, tests, traffic, transportation

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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 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:
This paper presents the results of a research project to determine the long-term performance of wood fibre embankments, that were constructed by the Washington State Department of Transportation (WSDOT) beginning in 1972. At the time of their construction, concern existed that wood fibre fills would only provide a 15 to 20 year service life.Performance of existing wood fibre fills was evaluated based on thequality of the wood fibre material, quality of the effluent, and condition ofthe pavement. A visual classification system rating the wood fibre from freshto completely decomposed was developed and used in order to establish acriteria from which all wood fibre mater.ia1 could be -rated.. Visual examinationin conjunction with laboratory tests were used as determining aspects for theeffluent quality. The WSDOT Pavement Management System was used to evaluate relative pavement performance. Site descriptions are presented giving specificcharacteristics and properties of the fills inventoried, An analysis of t h i sinformation was done to determine the effectiveness of the fills.Over half the wood fibre samples were found to be nearly fresh or freshand none w e found to be completely decomposed. In all but one case, thepavement quality over the wood fibre fills surpassed the comparative highwaysegment rating indicating the wood fill\'s performance exceeded thatof the surrounding area. Generally, the surface water in the vicinity of thewood fibre was found to be clean and pure indicating no adverse impact ofeffluent. Given the above findings, embankments constructed of wood fibre werefound to perform well over ahnost a 20. year period. Service life in excess of50 years can be expected - of wood fibre fills.

Authors:
Kilian,A. P., Ferry,C. D.

Keywords:
analysis, condition, construction, developed, effectiveness, Embankments, evaluation, impact, Leachate, management, management system, pavement, pavement management, pavement performance, pavements, performance, performance evaluation, project, quality, research, tests, transportation, Washington, Washington state, Wood fibre, WSDOT

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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:
A comparative study of ten pile driving formulas is described. The formulas are the Danish, ENR, Eytelwein, Gates, Hiley, Janbu, Navy-McKay, PCUBC, and Weisbach. The ultimate load for each of sixty-three load tests was determined using the Q-D over 30 method to determine ultimate capacity.The predicted pile capacity was by the measured capacity to obtain normalized values. analysis for coefficient of variation were performed on the logarithm of the normal capacities to determine which formula provided the most consistent prediction of pile capacity. The Gates formula proved to be the best and the widely used one of the worst with a coefficient of variation approximately 2-3 times higher than that for the Gates formula.

Authors:
Fragaszy,R. J., Higgins,J. D., Argo,J. D.

Keywords:
analysis, factor of safety, pile capacity, pile driving formulas, pile formulas, pile-driving, piles, prediction, tests, ultimate capacity

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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 report describes the construction of experimental asphalt-rubber open-qraded friction course overlays on I-5 in Vancouver, Washington. A 1200 foot section of open-graded pavement was included as a control section. Evaluations will be conducted over a period of three years to measure the performance of the rubber and polymer sections against the control section of conventional open-graded pavement.Initial observations and tests show no significant differences between the control and the asphalt-rubber and polymer sections.

Authors:
Anderson,K. W.

Keywords:
asphalt, asphalt pavement, Asphalt-Rubber, construction, control, evaluation, experimental, friction, friction course, open-graded, overlay, overlays, pavement, performance, PlusRide, polymer, rubber, tests, Washington

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Abstract:
The use of liquid anti-stripping additives (LAA) for reducing moisture damage in asphalt concrete pavements was evaluated using pavement cores from pairs of projects with-and-without LAA. Results were analyzed using the tensile strength ratio (TSR). In addition, a diazo-dye for determining the presence and concentration of LAA was attempted to access the value or the test as a field procedure. The chemical additive detection tests proved inclusive, but the TSR analysis gave a positive indication of the need for the use of LAA in the wetter environments of the state, For drier environments and for low traffic volumes, use of LAA may not be cost effective. The indirect tensile test was judged to be a potentially valuable tool for statewide use in the evaluation of stripping additive needs.

Authors:
Malsch,D. A.

Keywords:
additive, analysis, anti-stripping agents, asphalt, asphalt concrete, Asphalt Concrete pavement, bituminous concrete, Chemical, concrete, cost, cost effective, damage, detection, diazo-dye test, effectiveness, environment, evaluation, indirect tension test, moisture damage, pavement, pavement life, pavements, project, strength, stripping, tests, traffic, traffic volumes, volume

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Abstract:
Two forms of pavement distress were noted on recent asphalt concrete overlay projects. A general loss of wearing surface under traffic action, termed surface ravelling, was observed on three projects starting the first season after construction.Two forms of pavement distress were noted on recent asphalt concrete overlay projects. A general loss of wearing surface under traffic action, termed surface ravelling, was observed on three projects starting the first season after construction. A concentrated, local loss of surface material in narrow longitudinal strips, designated as strip ravel ing, was observed on four projects approximately the second season after completion. Construction record reviews and field testing and sampling of these projects along with four undistressed projects were made to define the construction methods and equipment used and to obtain samples from areas of good and bad pavement condition. These samples were tested to determine the strength of the compacted mix, and of the aggregate and asphalt constituents. Common factors from the projects showing surface ravelling were a thin lift pavement overlay placed late in the paving season with a tendency toward less than optimum asphalt content. The resulting pavement had high air void content and was readily abraded by traffic during ensuing severe winter weather. Recurrence of this type of problem can best be prevented by increased emphasis on proper compaction and mix design. Remedial work on the present projects should be directed toward a seal coat application. Strip ravelled projects were found to have similar pavement properties in ravel and non-ravel led sections and general to be within desirable limits. Lower strength in resilient modulus tests and physically observed asphalt stripping in the ravelled sections indicate a localized failure of the asphalt aggregate bond. The failure occurrence in narrow longitudinal strips indicates a cause associated with paving operations--possibly differential compaction or hydrocarbon contamination. Preventive measures should ensure uniform compaction and more thorough checking of stripping tendencies. Corrective measures will require continued patching and possibly removal and replacement of affected pavement.

Authors:
Gietz,R. H.

Keywords:
aggregate, asphalt, asphalt concrete, asphalt pavement, compaction, concrete, condition, construction, construction methods, contamination, design, Distress, investigaton, overlay, pavement, resilient modulus, sampling, season, strength, tests, traffic, winter

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Abstract:
The Alternate Methods of Avalanche control project has been funded by the Washington State Highway Commission since August 1974 in order to develop simple, reliable and repeatable methods of triggering avalanche release which are free from the storage, handling and availability problems of explosives and artillery shells and which can be readily applied to avalanche paths typical to many smaller ones causing hazards for highways.The Alternate Methods of Avalanche Control project has been funded by the Washington State Highway Commission since August 1974 in order to develop simple, reliable and repeatable methods of triggering avalanche release which are free from the storage, and availability problems of explosives and artillery and which can readily be applied to avalanche paths typical of the many ones causing frequent hazards for highways. The research involved tests in both Washington and Colorado to permit evaluation of the control methods in diverse climates and snow conditions, leading to more generally applicable results than could be obtained at a single site. The technical and scientific aspects of the work in Colorado were coordinated by the San Juan Avalanche Project of the University of Colorado. Field work in Washington state and the general supervision of the program and the engineering design were carried out by the University of Washington Geophysics Program. The U.S. Forest Service at Utah, also joined in a cooperative test of our methods and equipment. This Final Report describes the tests and the results of the entire project.

Authors:
LaChapplle,E. R., Bell,D. B., Johnson,J. B., Lindsay,R. W., Sackett,E. M.

Keywords:
availability, avalanche, snow, weather, stress waves, condition, control, design, equipment, evaluation, hazard, highway, Highways, program, research, tests, Washington, Washington state

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Abstract:
A series of measurements was undertaken in the summer and fall of 1977 to determine the noise radiated by a wide variety of cars and trucks, and the effect of an acoustic wall, or barrier, on suppressing the transmission of that noise. The assumption of the \"correct\" effective radiating height was found to be the most critical parameter in making the calculations agree with the measured results. The \"best height\" value varied greatly from vehicle to vehicle, and with speed, load, and throttle setting for a given vehicle. The variability of this parameter made it impossible (solely from these tests) to assess such considerations as whether Fresnel\'s or Maekawa\'s curves should be used to calculate the attenuation produced by the wall.The most noteworthy observation from this study is that newer trucks not only are quieter (to meet noise radiation standards) but have an effective radiating height as low as 2 ft compared to as much as 11 ft for older trucks. \'Thus, as the newer types of trucks become predominant in the highway traffic mix, the effectiveness of walls and barriers in shielding the community from noise will increase considerably.This is good news, because wall effectiveness has been marginal at best for pre-1970 trucks because of their radiation heights.

Authors:
Foss,R. N.

Keywords:
attenuation, barrier, barriers, effectiveness, Fresenel diffraction, highway, Highway acoustics, noise, noise screens, Noise supression, speed, tests, traffic, truck, trucks, vehicle noise, walls

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Abstract:
A photogrammetric monitoring method of structural deformation has been developed during the course of this project. The Gabion Wall which is part of the I-90 project has been used as the site for practical tests of the theorectical development. The monitoring consists of photographing the structure from three camera stations with KA-2 f=24" camera. The camera has been modified to a plate camera to provide the maxium accuracy.The methodology consists of the geodetic determination of the camera location and the orientation and photogrammetric determination of targets (natural and artificial) on the structure. During the course of this project more than 100 target locations were determined by three dimensional coordinates. the maximum error was found to be + 3/4 inch; the average, 1/2 inch. This represents a relative accuracy of from 1/58,00 to 1/120,00 of the photographic distance.Using the actual construction site for research has permitted immediate implementation. The instrumentation as well as the methodology along with the computer program has been transmitted to the Washington State Highway Department and their Photogrammetric Branch has been assisted in the implementation.

Authors:
Veress,S. A., Flint,E. E., Sun,L. L., Jinina,C.

Keywords:
camera, computer, computer program, construction, developed, development, Error, Gabion, highway, methodology, monitoring, Photogrammetry, Gabion Wall, deflection, camera stations, orientation matrices, space intersection space resection, program, project, research, tests, Washington, Washington state

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Abstract:
A collection of reports resulting from the second year's study. Reports are entitled:1. Air Bag System by E.R. LaChapelle, C.R. Morig and P.L. Taylor 2. Gas Exploder System by E.R. LaChapelle, C.R. Morig, and P.L. Taylor 3. Vibrator Tests by E.R. LaChapelle, C.R. Morig and P.L. Taylor 4. Mechanical Resonance of Snow by J.B. Johnson 5. Interface Modification Field Tests by E. R. LaChapelle 6. Approximate Solutions for the Interruption of the Creep and Glide of a snowpack by Rigid Structures by J.A. Langdon

Authors:
LaChapplle,E. R., Johnson,J. B., Langdon,J. A., Morig,C. R.

Keywords:
avalanche, snow, weather, creep, glide, control, field test, interim, structures, tests

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Abstract:
A collection of reports resulting from the first year's study Alternate Methods of Avalanche Control. The reports are entitled:1. Air Bag System by E. R. LaChappelle and P.L. Taylor2. Gas Exploder System by E. R. LaChappelle and P. L. Taylor3. Snow Behavior Behind a Continuous Avalanche Defense Structure by J.A. Langdon.4. Interface Modification Field Tests by E. R. LaChappelle5. Mechanical Resonance of Snow by J. B. Johnson and R. J. Evans6. The 1974-75 Winter by M. B. Moore

Authors:
Brown,C. B., Evans,R. J., Johnson,B., Langdon,A., Moore,B., Taylor,L.

Keywords:
alternative, avalanche, avalanche forecasting, snow, weather, creep, glide, behavior, control, field test, interim, tests, winter

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Abstract:
Tests were conducted on various pavements t o investigate the correlation between measurements obtained using the Impulse Index Computer and pavement condition as determined by other means. Benkelman Beam deflection measurements and Impulse Index measurements are compared along with Washington State Pavement Rating System results. Effect of temperature on the apparent Impulse Index is evaluated..

Authors:
Brands,F., Cook,C. J.

Keywords:
Benkleman beam, computer, condition, Deflection test, impulse index, impulse testing, index, pavement, pavement condition, pavement deflection, pavement evaluation, pavement maintenance, pavements, systems, temperature, tests, Washington, Washington state

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Abstract:
This study was conducted to collect data on the operational characteristics of highway, snow, and studded snow tires and other winter traction aids. The objective of the study was to perform various vehicle maneuvers to evaluate the tire characteristics on wet and dry pavement surfaces. Tests took place on the Washington State Patrol Driver Training Course at Sanderson Field, located west of Shelton, Washington. The testing was done with the cooperation of the Washington State Patrol who furnished personnel and equipment to assist in this research effort.This test maneuvers evaluated during the study are as follows:Test No. 1 Maneuvering (Serpentine Course)Test No. 2 Hairpin CurveTest No. 3 High Speed Lane ChangeTest No. 4 Locked-Wheel StopIn addition to the three types described above, other new traction type products and tires were evaluated. These consisted of studded snow tires with "Norfin" studs, and Garnet impregnated snow tires. Studded tires on all four wheels were also evaluated, at the request of the Washington State Patrol. This combination is used by Troopers assigned to mountain highway passes and areas where there is a large buildup of snow and ice during the winter. This report consists of two areas of evaluation. One involves tire combinations (front and rear) and the other is the evaluation of individual tire types. In addition to these two areas, a separate section is devoted to the tire and vehicle characteristics of Washington State Patrol's vehicle when compared with a Department of Highway's Motor Pool Vehicle. Included also is the test vehicles' description.

Authors:
Toney,Carl A.

Keywords:
data, equipment, evaluation, highway, No Keywords found in report, pavement, pavement surface, research, snow, speed, studded tire, studded tires, studs, tests, tire, tires, traction, training, Washington, Washington state, winter

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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:
This report describes the results obtained from Experimental Ring No. 2, the first ring of a three-ring tests series on treated bases at the Washington State University Test Track. This experiment was concerned with studying the effects of controlled wheel load repetitions on untreated, emulsion, and specialaggregate asphalt - treated bases of four varying thicknesses. Construction, instrumentation, results , and conclusions are described and drawn. Benkelman beam, LVDT, strain gages, pressure cells and moisture tensiometers were used to measure deflections , strains , stresses and moisture. Maximum values are tabulated. Temperatures were also recorded. Testing can be divided into two time periods - fall of 1966 and spring of 1967. Values obtained from instruments show that different conditions existed during those testing periods, and that deflections , strains and stresses were two to four times higher in the spring than in the fall. Modes of failure were also different . Equivalencies between the different base materials were established. Other conclusions were drawn. Since this is a continuing experiment, it should be emphasized that results and conclusions are subject to change, depending upon data from the remaining experimental rings.

Authors:
Krukar,M., Cook,J. C.

Keywords:
asphalt, base, condition, construction, data, experimental, materials, pavement, pressure, research, strains, stresses, temperature, test track, tests, volume, Washington, Washington state

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Abstract:
Using full-scale construction equipment and truck loadings on a circular track of 260 feet circumference, evaluation of various base thicknesses and types has been accomplished in this first of a series of tests. Fractured and non-fractured aggregatre, treated and untreated bases, asphaltic and portland cement type bases are used. Results of the firest ring indicate type of failure under varied enviornmental conditions with pavement systems subjected to millions of load applications. Difficulties in determining comparative equivalencies are discussed. Instrumentations used and possibilities for future use in rational design are reported.

Authors:
Riedesel,G. A.

Keywords:
applications, base, condition, construction, design, equipment, evaluation, experimental, pavement, research, systems, test track, tests, truck, truck loadings, volume

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