A Study on Improvement to Increase Efficiency of U–Turn Opening on Charan Sanit Wong Road at Bang O Fire Station U–Turn

Abstract

The U–Turn is a risky point where there are frequent road accidents. There are many factors leading to the problem of the U–turn such as the physical characteristics of the U–turn, location of U–turn median opening, insufficient sight distance, risk spot around the U–turn without traffic management and safety and factors caused by the driver. This paper presents the results of a study on improvement to increase efficiency of U–Turn Opening on Charan Sanit Wong Road at Bang O Fire Station U–Turn. By studying the improvement pattern of the U–turn from the past to the present and the pattern of improvement measure. Traffic microsimulation model was developed using VISSIM software and evaluated the traffic efficiency. The results were analyzed to determine the Time–To–Collision (TTC) using the SSAM program to assess traffic safety from the number of conflict points. The results showed the pattern of improvement measure with improved physical characteristics by increasing the length of the storage lane and restricted U–Turn for motorcycle measure could increase traffic efficiency. The average travel time was reduced by 1% and 10% and reduced the average delay by 12% and 31% in the directions to Rama VII and Pinklao, respectively. The safety analysis results showed the pattern of improvement measure which has a Time–To–Collision (TTC) value of 0.88 seconds and has the least number of conflicts point compared to previous improvement pattern.