A Performance Evaluation of Solar Power Radar Speed Sign on Burapha Withi Expressway

Abstract

This study aims to evaluate the performance of solar power radar speed sign before and after the installation at Km.14+600 inbound, Km.24+100 outbound and Km.32+500 inbound which are considered as the high-risk accident locations on Burapha Withi Expressway. The result indicates that vehicle speed in the study areas varies by vehicle type and location. After comparing the 85th percentile speed with the speed limit according to the Traffic Act B.E. 2522, the result shows that most of the vehicles exceed the speed limit. Considering the comparison of the 85th percentile speed between before and after the installation of the solar power radar speed sign, this study reveals that vehicle speed tends to reduce by approximately 2.72%. However, it is still above the speed limit. Therefore, Expressway Authority of Thailand, as an administration organization, should consider setting up the appropriate speed limit on expressway as well as improving physical appearance and appropriate speed control countermeasures. The contribution in this study will lead to the initiation of the countermeasure against the over speeding and reduce the accidents caused by vehicles exceeding the speed limit on the expressway.