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Limited field investigations have evaluated the impact of traffic on the snow melting capacity of salts. This paper will describe an extensive field study that includes 1,200 tests that are conducted during 100 snow events over three winter seasons (2012, 2013, and 2014) to quantify the traffic impact on snow melting capacity. The tests will be conducted in an active parking lot, and on parking stalls and driveways, which could increase the applicability of the results to real-world scenarios. The deicing performance of salt will be compared between both areas with different traffic patterns for bare pavement regain time (BPRT). The developed model quantified the reduction in BPRT from 21% for a low traffic volume of 5 vehicles/h to an 86% reduction for a high traffic volume of 50 vehicles/h. The deicing performance models that were calibrated for parking stalls and driveways could be directly used to determine the most cost-effective application rates to treat parking lots and sidewalks based on specific weather, facilities, and traffic conditions. [ABSTRACT FROM AUTHOR]

In recent decades, road weather information systems (RWISs) have gained in popularity with road maintenance authorities. However, RWIS stations only provide point measurements that are often unrepresentative of distant surrounding areas. To address such limitations, this study employs a hybrid geostatistical interpolation method, regression kriging (RK), to fill in the large spatial gaps at unmonitored locations. Road surface temperature (RST) data collected by an automated vehicle system along selected interstate highways were used to model the RST spatial variation patterns via semivariograms, which were then used to interpolate the conditions in between RWIS stations. Cross-validation results indicated that RK successfully captured the spatial variation of RST along the highway segment. The nugget-to-sill ratio obtained from semivariograms was further utilized to characterize the weather events, and the results implied that stronger winds and heavier rainfalls were likely to form a stronger spatial dependence within RST. The findings of this research contribute to better understanding of the influences of meteorological factors in RST as well as improved models for inferring the road surface conditions between RWIS stations. [ABSTRACT FROM AUTHOR]

Focuses on a study which suggested the use of probe vehicles to provide estimates of link travel times as a means of obtaining travel times within signalized networks for use in advanced travel information systems (ATIS). Analytical estimation of expected delay of probe vehicles; Bias in the sample of probe reports; Effect of bias within a simple linear network; Conclusions and recommendations.