Abstract: According to the rectangular coordinate K-L, there are a great many different function expressions of OA to join the final point of a straight-line and the starting point of a circular curve. These expressions may be used for deriving a transition curve of highway. They can be a cube of parabola, an algebraic expression of sine function, 5th, 6th and nth power function of algebraic expressions. The author recommand the 5th power function of algebraic expression as a transition curve of highway after analyzing and comparing with other patterns.

摘要： 在K-L坐标系中,对应于直线终点的O点和圆曲线始点的A点,可以以不同的曲线相连接。本文从连接曲线的不同函数表达式推导出三次抛物线、含有正弦函数的代数式、n次幂函数、五次代数式和六次代数式公路缓和曲线公式。对其线型质量作了分析,并与相应的研究成果作了对比。作者推荐五次代数式做为公路缓和曲线。