STUDY ON THE INFLUENCE OF ROAD GEOMETRIC CONDITIONS TO VEHICLE SPEED

• Main Author: TRI MUKTI - NIM: 35012006, ELSA
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/26922
• Institution: Institut Teknologi Bandung

<p align="justify">Road geometric elements are designed bu using a consistent design speed, wherein the road designer generally maintains a constant design speed along the way as a means of obtaining design consistency to reduce the frequency of speed changes along road. There are two speed-based approaches used in evaluating design consistency, namely the design speed approach and the operating speed approach. However, based on the results of research that has been done previously, it was found that the method based on the design speed does not guarantee a consistency. Therefore, using the operating speed prediction in the design phase of the design geometric process has been the focus of significant research in recent years. Research on the operation speed prediction has been done in various countries by developing a model of operating speed prediction. The purpose of the development an operating speed prediction model is to find the relationship between operating speed and geometric design elements. <br /> <br /> <br /> The main objective of this research is to develop vehicle operating speed prediction model influenced by the combination of horizontal alignment and vertical alignment parameters for the case of intercity road 2-lane two-way undivided (2/2 UD). The location of the research on the Pontianak-Tayan road (West Kalimantan province) with the type of vehicle observed is light vehicles and heavy vehicles. <br /> <br /> <br /> Based on the results of the research, it is found that there are differences in the characteristics of vehicle operating speed when passing a curve with a different combination of horizontal alignment and vertical alignment. Based on the results of statistical tests, there was no significant difference between the speed of vehicle operation at the beginning point, midpoint and end point of a curve, both for light vehicles and for heavy vehicles. The operating speed prediction model for light vehicles is affected by radius curvature (R) parameter, and heavy vehicles are affected by radius curvature (R) and vertical gradients (G) parameters, where the radius curvature (R) and vertical gradients (G) affect the operating speed positively. Sensitivity analysis shows that the operating speed is more sensitive to the change in radius curvature (R) than the change in vertical gradient (G). Based on the design consistency analysis, it is found that at the location where the accident occurred, it has poor design consistency criteria.<p align="justify">