Research News

Mechanisms Involved in the Removal of Heavy Metals from Stormwater via Lignocellulosic Filtration Media

In the Pacific Northwest, elevated soluble zinc and copper concentrations originating from urban stormwater runoff pose a significant threat to native salmon and steelhead populations. In response to urbanization, existing stormwater infrastructure needs to be upgraded to treat non-point source pollution, including soluble metals, before they enter receiving waters. This project aimed to provide sustainable design suggestions for urban stormwater remediation at Washington State Ferry terminals. Researchers conducted laboratory and field-scale column tests to recommend specific types of plant filtration media for copper and zinc adsorption.

Recycled Glass Fiber Reinforced Polymer Composites Incorporated in Mortar for Improved Mechanical Performance

In this study, recycled glass fiber reinforced polymer composites from end-of-life wind turbine blades were evaluated as a replacement for sand in cement mortar. In the last two decades, glass-based materials in the form of powder or fibers from recycled bottles and other products, and more recently recycled glass fiber reinforced polymer (GFRP) composites from end-of-life products or industrial waste, have been incorporated into cement-based mixtures in various proof-of-concept designs. To understand better how GFRP would affect the properties of mortar, researchers conducted a feasibility study to compare different GFRP sizes and percentages.

Preliminary Procedure for the Structural Design of Pervious Concrete Pavements

The growing popularity of pervious concrete (PC) pavement applications has increased the need for establishing its mechanical properties and understanding their relationships with measurable properties for the purposes of designing layer thickness. In this project researchers developed multi-variable linear regression models to predict strength properties for pavement thickness design and developed a recommended thickness design database for low-traffic-volume PC pavements.

Developing Connections for Longitudinal Joints between Deck Bulb Tees—Development of UHPC Mixes with Local Materials

In past decades, many state departments of transportation and the Federal Highway Administration have begun working with ultra-high performance concrete (UHPC), an advanced cementitious material. WSDOT has not used UHPC in highway bridge applications, such as connection joints for precast concrete decks and girders, because of the concrete’s high cost and because of general lack of experience with it. The goal of this project was to develop a UHPC mixture using materials available locally and domestically as an alternative to commercially available, pre-packaged UHPC products.

Use of Electronic Fare Transaction Data for Corridor Planning

Transit agencies across the nation are increasingly using electronic fare payment methods to speed passenger boarding, reduce the cost of fare collection, provide various other rider benefits, and support more complex fare transactions. This project, jointly sponsored by WSDOT and Sound Transit, explored the use of fare transaction data gathered from the Puget Sound region’s ORCA transit cards, in combination with other sources of transit and non-transit-related data, to produce information that can significantly benefit transit operations and the transportation planning processes for both transit agencies and metropolitan planning organizations.

Safe Main Street Highways: Analyses of Collisions Involving Pedestrians and Bicyclists in Washington State

What could make main street highways safer for alternative modes such as walking and bicycling? Main street highways (MSHs) are stretches of state highways that also act as main streets for local populations. This study looked at where pedestrian and bicyclist collisions most often occur on MSHs and developed models for estimating socio-economic and environmental predictors of collision locations so that WSDOT and local agencies can improve pedestrian and bicyclist safety measures.

NCHRP 08-98: Guide for Identifying, Classifying, Evaluating, and Mitigating Truck Freight Bottlenecks

The demand for truck transportation increases alongside growth in population and economic activity. As both truck and passenger traffic outstrip roadway capacity, the result is congestion, which the freight community experiences as truck bottlenecks. This NCHRP project produced a Guidebook that provides state-of-the-practice information to transportation professionals on practices and measures for identifying, classifying, evaluating, and mitigating truck freight bottlenecks. The intent is to help decision-makers in developing cost-effective solutions to address different types of truck freight bottlenecks.

Traffic Monitoring Practices Guide for Canadian Provinces and Municipalities

The Traffic Monitoring Practices Guide for Canadian Provinces and Municipalities provides the first national-level guidance on the planning, design, and implementation of traffic monitoring programs for Canadian provinces and municipalities. The Guide will assist agencies with upgrading their traffic monitoring programs and may ultimately culminate in more consistent, nationally relevant guidance for monitoring traffic.

Portland Cement Concrete Material Characterization for Pavement ME Design Implementation in Idaho

This project began development of a database of portland cement concrete material inputs specific to Idaho in preparation for Idaho’s implementation of the AASHTOWare Pavement ME Design software for designing rigid pavements. The Idaho Transportation Department (ITD is transitioning from pavement design procedures based on the AASHTO 1993 Design Guide to AASHTOWare Pavement ME Design (Pavement ME). Pavement ME requires the definition of more than 100 design input parameters. On the basis of this project’s laboratory test results, the report recommends proper values for all PCC Pavement ME material inputs.

Best Practices of Using Shotcrete for Wall Fascia and Slope Stabilization, Phase I Study

Shotcrete, concrete applied pneumatically at high velocity, has become attractive because of its potential for saving cost and construction time when used to replace cast-in-place (CIP) concrete for retaining walls and slope stabilization. However, it also has potential drawbacks that raise concerns about its durability. This project was a first-phase effort in determining the best practices for using shotcrete for wall fascia built with soil nails and soldier piles. With the increasing desire of highway agencies to use shotcrete to save time and money, such information will be helpful to them in achieving the best structural quality and durability.

Washington State Transportation Center