用四次曲线取代复曲线

Replace Compound Curve with Quartic Curve

在同向曲线间直线距离不足的路段采用以一条四次曲线敷设的形式 ,使曲率变化连续 ,线形更加顺适、美观。

This paper suggests to lay a quartic curve between adjacent curves in one direction when there is not enough straight distance, instead of the compound curve which is measured complicatedly. The curvature of the quartic curve varies continuously, which makes the line?form smoother and more artistic.