Impact assessments of highway construction work zones (CWZs) are mandated for all federally funded highway infrastructure improvement projects. However, most existing approaches are ad hoc or project specific, so they are incapable of being benchmarked for any particular spatial region. A novel multicontextual approach to modeling the traffic impact of urban highway CWZs is proposed and tested in this paper. The proposed approach is unique because it models the impact of CWZ operations through a multicontextual quantitative method using big data for improved accuracy. In this study, a machine-learning technique was adopted to predict long-term traffic flow rates and the corresponding truck percentages. With the use of these predicted values, stereotypical patterns of traffic volume-to-capacity ratios were created for typical urban nighttime closures. Third-order curve-fitting models to achieve potential work zone travel time delays in heavily trafficked large urban cores were then developed and validated. This study will greatly help state and local governments and the general traveling public in major cities know the potential traffic flow resulting from construction and thereby facilitate progress on highway improvement projects with the better-informed work zone traffic flow and thus improve safety and mobility in and between CWZs.

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Variation of moisture content within substructures of pavements plays a key role in controlling load bearing capacity tied to adjust strength parameter and resilient modulus of subsoil layers to corresponding moisture level. This paper presents efforts to develop the LoadGage computer program for estimating pavement load bearing capacity accounting for in-situ moisture condition. From results of plate bearing tests, it was observed that the current modified triaxial design method which has been adopted by the Texas Department of Transportation (TxDOT) as a design check procedure relatively underestimates pavement load bearing capacity. In view of the moisture conditioning that samples undergo in the existing triaxial test method, the adjustment of subgrade strength parameters based on the soil-water characteristic curve provided a rational approach for considering the difference in moisture conditions between laboratory tests conducted to characterize strength parameters for pavement design and the field conditions expected in-service. Validating the LoadGage program was achieved via a series of plate bearing tests, and it revealed reasonable estimations compared to field observations especially in pavements built with stabilized layers.

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