在旧的营业线上,尤其是山区铁路,还存在一些复曲线。拨正这些曲线的困难之一,在于确定复曲线公切点或连接两园曲线之中间缓和曲线的始、终点位置,以及计算这些部位的设计正矢。在《确定缓和曲线始、终点位置的简易计算法》一文中,已经叙述了确定这些点位置的方法,本文介绍如何计算这些部位的设计正矢。在下文中,除特别指明者外,采用以下符号: In the old business lines, especially mountain railway, there are still some complex curve. One of the difficulties in dialing these curves is the determination of the beginning and ending positions of the common tangency point of the complex curve or of the middle transition curve connecting the two circular curves and the design positive vectors for calculating these points. In the article “A Simple Calculation Method to Determine the Starting and End Locations of Transition Curves,” we have described how to determine the placement of these points. This article describes how to calculate the design positive vectors for these locations. In the following, the following notations are used unless otherwise specified: