本文介绍了萧甬线软土地基的特点，叙述了在其增建第二线线间距的选择及地基加固方案的确定，结合具体实际和实践，行之有效地解决一系列问题。

The paper introduces the characteristic of the soft ground along the Xiaoshan-Ningbo railway. The descriptions are concerned with how to select distance between the centers of double track lines and how to determine a scheme of consolidated subgrade when its second railway line is added. And，combined with the particular situation and the practicality， a series of effective solving measures are proposed.