Research on Speed Limit of Two-Lane Highway of Mountain Area

Abstract

The paper investigates the effects of the road geometry parameters and the driver psychosocial reaction behaviors on driving safety of vehicles on the two-lane highway of mountain area. Firstly, the equivalent accident rate, P, is put forward as driving safety indicator, and the parameter sensitive analysis are performed between P and road geometry parameters including curve radius, slope and length, then the estimation model and evaluation criterion of P is established. Secondly, the psychosocial reaction behavior index, N, is provided as ride comfort indicator, and the evaluation model of N is established by relating N with road geometry parameters and driving speed. Finally, the two kinds of limiting condition including highest safety of the general bending, slope sections and lowest safety of the sharp curve, steep sections are present and the corresponding the driving speed is calculated. The analysis show that when V=35km/h in the most secure particular curved, the optimum driving safety and comfort can be achieved. As well, the maximum speed will be 10km/h in the lowest ones.