STUDY OF SPEED REDUCTION MEASURES: CASE STUDY ON NATIONAL HIGHWAY NO. 12, BAN KRANG INTERSECTION – INDOCHINA INTERSECTION, PHITSANULOK PROVINCE

Abstract

     This research aims to study the efficiency of vehicle speed reduction measures according to the law on National Highway No. 12, from Ban Krang Intersection - Indochina Intersection, Phitsanulok Province at a speed limit of 80 km/h through the city, a distance of 14.5 km. There are 4 data collection locations, namely, point 1 at km. 225 – km. 228, point 2 km. 228 – km. 233, point 3 km. 233 – km. 237, and point 4 km. 237 – km. 240 which related to the determination of 3 types of speed reduction measures, namely 1) warning signs, 2) speed cameras, and 3) rumble strips with warning signs for off- peak 6 hours per day. The results of the study found that the majority of motorists used the speed limit in both directions. In the direction A (Ban Krang Intersection - Indochina Intersection), drivers used the 85^th percentile speed, equal to 85.3 km/h, 79.4 km/h, 86.2 km/h, and 85.1 km/h, respectively, for direction B (Indochina Intersection - Ban Krang Intersection) is equal to 89.5 km/h, 80.0 km/h, 86.5 km/h, and 85.2 km/h, respectively, with only in point 2 (speed camera) where drivers follow the speed limit. The researcher therefore recommends those involved or responsible for road safety to develop a new road speed reduction measure to enhance travel safety and make drivers comply with the speed limit.