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This paper focuses on successful application of permeable pavement design and performance with special emphasis on stormwater management, water quality benefits, and identification of knowledge and data gaps. The paper provides a summary of the current practice and design methods, discusses the potential application of permeable pavement for highway environment, summarizes the research progress documented in the literature related to mixed design, hydrologic performance, maintenance, water quality benefits, identifies knowledge gaps and unresolved issues, and explores the future direction in permeable pavement application. While there are many successful permeable pavement installations in parking lots and commercial areas with low speed and light traffic loads, only a handful of demonstration projects and simulation studies have evaluated the use of permeable pavements for highways and urban roads with higher vehicle speeds and heavier loads. Those studies and simulations have shown promising results.View the NCST Project Webpage

Under current provision of the Clean Water Act (CWA) and the amended National Pollution Discharge Elimination System (NPDES) all communities with populations of 10,000 or more, which includes nearly all jurisdictions in the United States, are required to regulate and control the discharge of urban stormwater into receiving water bodies. The CWA and related regulatory compliances and societal demands for clean water have exerted a tremendous amount of pressure on stormwater runoff dischargers throughout the United States to develop innovative stormwater treatment and management strategies.A more environmentally beneficial and cost-effective approach to capturing, treating, and slowing down water runoff generated by road surfaces is the use of a full depth permeable pavement shoulder design. Under this proposed design, most if not all runoff will be retained within the shoulder and there would not be a need for additional treatment. The use of permeable pavement shoulders in highly urbanized areas is particularly beneficial since finding sufficient land area to implement other solutions (such as infiltration or detention basins) is difficult.This policy brief summarizes findings from the research project on successful application of permeable pavement design and performance with special emphasis on stormwater management, water quality benefits, and identification of knowledge and data gaps. View the NCST Project Webpage

During concrete pavement construction, comprehensive information on concrete strength development is necessary for knowledgeable scheduling decisions. To improve in situ strength estimation, nondestructive tests can be combined to maximize available information and increase collection efficiency. Ultrasonic testing has a higher accuracy in strength estimation for early age concrete and the external device allows for more data to be easily collected, while maturity testing can use temperature models to predict strength development. A procedure was created that combines these methods and their strength models in the laboratory for improved and increased field strength data. Using the procedure allows more data to be collected with greater accuracy and provides an adjustable, predicted strength development. This improves the efficiency of fast-track construction projects without resorting to costly alternatives by providing more information on strength development of in situ concrete than traditional strength testing or nondestructive methods individually. [ABSTRACT FROM AUTHOR]

This paper presents a new numerical procedure for the determination of the viscoelastic compliance properties of a matrix phase from a simple three-point bending test on a composite beam. The composite is modeled as elastic inclusions randomly dispersed throughout a viscoelastic matrix. It is also assumed that the spatial distribution of the inclusions in the composite is known or can be determined. Zevin's method of iterative functions is proposed for the determination of the matrix properties. Following a detailed explanation of the proposed scheme, a numerical verification is performed using three-dimensional finite-element (FE) analysis simulations. The proposed scheme was applied to the experimentally obtained creep compliance of the asphalt concrete beam. The obtained viscoelastic properties of the asphalt binder matrix phase were used as input into the FE model to simulate the behavior of the composite beam. An excellent comparison between the experimental data and the predicted beam deflections was observed. This shows that the proposed method is robust and it can be implemented to solve identification problems for viscoelastic composite materials. DOI: 10.1061/(ASCE)EM. 1943-7889.0000126 CE Database subject headings: Elasticity; Viscoelasticity; Numerical analysis; Asphalts; Mixtures; Composite materials; Pavements. Author keywords: Elasticity; Viscoelasticity; Numerical analysis; Asphalts; Mixtures; Composite materials; Pavements.

An algorithm for elastic reactions that can be used to compute other force or deformation variables was reviewed. This algorithm was then compared to a previous solution by Kharlab in 1963 that computes the response of structures undergoing continuous changes under time-dependent loads. This was based on his principle that if the superposition is satisfied, then (i + 1)th delayed restraint acts on the system like it was the first and only restraint.