三次样条曲线在互通式立交匝道端部设计中的应用

Application of Cubic Curve to Exit and Entrance at Interchange

高速公路互通式立交设计 ,对于直线上的车道驶出 (驶入 )道口 ,匝道是按一定的斜率偏离主线的 ,这时斜行的变速车道是一条直线 ,而对于曲线上的驶出 (驶入 )道口 ,变速车道不是直线而是按斜率规定的偏离度逐渐偏离主线的一条曲线。本文提出采用三次样条曲线来设计计算匝道端部曲线 。

?A ramp often deviates from the linear mainline with a certain slope in the exit or entrance of interchange, and the sloping speed-change lane of the ramp is a straight line. When the mainline is curved, a curved speed-change lane becomes necessary. This paper introduces a method for the design of the curved ramp using cubic curve and promotes its implementation.