Urban arterial level-of-service evaluation method in Taiwan

The modifications to the arterial level of service (LOS) method in the 1985 Highway Capacity Manual (1985 HCM) for use in Taiwan are presented. Street conditions and traffic characteristics in Taiwan are different from those in the U.S., therefore the 1985 HCM can not directly be used in Taiwan without adjustments. Street segment, turning movement, travel time and delay, traffic signal spacing, and effects of motorcycles on free flow speed were investigated to calibrate quantitative measures for modifying the arterial classification method as well as the definitions of urban arterial and arterial LOS measures. It was shown that the modified arterial evaluation method meets the actual conditions of Taiwan urban arterials and that the approach and considerations in modifying the 1985 HCM provide other countries an example in applying the 1985 HCM method for their local conditions.