HEAVY VEHICLES SPEED PROFILING ON URBAN EXPRESSWAY: THE CASE OF FEDERAL HIGHWAY

The presence of heavy vehicles on expressways will have an impact on the traffic performance. The geometrical design of expressways with the purpose of providing a better performance towards vehicles especially passenger cars, is also a prudent facility to the heavy vehicles, especially when it comes to speed. Though national allowable speed for heavy vehicles has been set, the actual situation may differ according to the general observation. This study attempts to explore the speed distribution of heavy vehicles typical urban expressways in Malaysia with Federal Highway Shah Alam-Kuala Lumpur being the case study.  Extensive data was collected through video recording before being abstracted and processed by utilizing the TRAIS software. Then, statistical analysis showing the speed distribution and profiling are presented. The results showed that in average heavy vehicles drive at speed of more than the allowable limit for the determined expressway section. The 85th percentile also indicates that thespecial speed limit of heavy vehicle on expressway is violated and therefore speeding enforcement would be appropriate instead of adjust in posted speed limit.