SUMMARY
Motorcycle lane has proved to be an effective engineering measure in reducing motorcycle crashes and fatalities. Its effectiveness stems from the fact that it helps mitigate the hazards of riding a motorcycle in a traffic stream, which have become a serious cause of death and injury in many countries.This research seeks to develop standardized configurations and widths for motorcycle lanes in Thailand. The optimum format for such a lane may be determined from the simulation of data relating to road accidents, traffic volumes and vehicle speeds.In practice, a range of initial lane widths were inputted into a traffic simulator program - in this case, the VISSIM 5.4 - whose output was analyzed to yield the relationship between MC volume, lane width and level of service (LOS). A pilot test was then performed on a stretch of actual road which had been installed with an MC lane of varying widths. Changes in vehicle speed were observed and employed to determine the relationship between lane width and the actual reduction in vehicle speed and the theoretical reduction in road accidents. Findings of the study point to an efficient lane width in the range of 2.0 to 3.0 m - for the shared lane configuration. For any width outside the said range, the benefit of the MC Lane would be eroded either by the intrusion of larger vehicles, or by the constraining effect of too narrow a lane. The authors also recommends the preferred width for an Exclusive MC Lane which may range from 3.0 to 4.0 m. The lane width of 3.0 m is found to be the most effective in reducing the speed of all traversing vehicles, even when compared with the 2.5 m or 3.5 m widths. With the 3.0 m option, the resulting reduction in speed can be as high as 17%; and reduction of accidents, up to 25%. In view of the aforementioned, the authors recommend configuring for the Shared Motorcycle Lane of 3.0 m with 2 sublanes of 1.5 m width, and for the Exclusive Motorcycle Lane 3.0 - 4.0 m with 2 sublanes of 1.5 to 2.0 m width.