Research On Method To Confirm Minimum Radius Of Circular Curve Of Mountain Expressway

For mountain expressway, especially the road used separate subgrade, because its geography, topography, ecological environment, etc. is particular, and the state of the automobile which driving up or down slope road is obviously different, the method to confirm minimum radius should be distinguishing from common road. For this reason, this text has done special research.This paper introduces the domestic and international study on the standard of alignment design at first, explains the research approach and the value of minimum radius of circular curve both at home and abroad, compares the route standards of the east and the west of our country.According to the principle of vehicle handling stability, this text studies the sport character and turnover condition of vehicle driving on circular curve. And this paper also using the 3-D vehicle model and the tire model studies the sideslip when the vehicle driving up or down. Then, this paper concludes the minimum radius of circular curve which can guarantee the automobile goes safely on mountain expressway at various kinds of road conditions (superelevation, vertical slope, adhere coefficient) and in different speeds.Finally, this paper compares and analyses the minimum radius of circular curve that can guarantee the automobile goes safely on mountain expressway and that has been prescribed in current technical standard of the highway engineering.