Comparison of 85th Percentile Operating Speed with different Median Segregation for Multilane Highways: A Case Study Kapar-Kuala Selangor

This study was conducted to compare the 85th percentile operating speed with different median segregation for multilane highways at three locations which are road with physical median, road with marking road median (deterioration) and road with marking road median. The site survey for this roadway is located at Jalan Kapar-Kuala Selangor, Selangor which is a multilane highways and road design standard is R5. Site condition in this area is flat terrain. Laser meter detector was used to collect the spot speed data of the various vehicle classes at three different locations with three different median segregations. Linear regression and paired t-test analysis was employed using Minitab statistical software to identify the significant difference in speed at the different median segregations. The results revealed that there is significant difference in the vehicle speed at location 1 where the physical median is present where the speed is 90.81 km/hr. Meanwhile, at location 2 and location 3 there are no significant difference in the vehicle speed. The vehicle speeds at these locations are 85.59 km/hr and 103.3 km/hr respectively. This indicates that the present of the different median segregation at the location has influence on the vehicle speed. Therefore, it is suggested that physical median segregation should be present at the multilane highways to increase the safety of the road users.