箱涵下穿既有铁路路基注浆补强效果数值分析

摘要

The box culvert is traversed under existing railway in the separate crossing construction of an expressway project in Henan. In order to assure the safety of train passing in jacking box culvert,the railway embankment surounding the box culvert is consolidated by using mortar grouting before construction. A three-dimensional model is set up by using the software Flac3D to simulate the jacking process of box culvert in order to investrgate the grouting effect. The computed results illustrate that the mortar grouting can make the settlement of railway embankment decrease appreciably and the settlement curves change gently,thus the train speed limit can be increased to a certain extent.%在某工程采用箱涵下穿既有线路方法建造立交道口时，为保证箱涵顶进过程中列车的通行安全，在顶进前对一定范围内的路基用水泥砂浆进行了注浆补强。为考察其效果，运用FLAC3D建立了一个三维模型，对箱涵顶进过程进行了数值模拟分析。模拟结果表明：箱涵周围土体注浆补强，可使顶进施工引起的线路沉降有所减小，且沉降曲线明显变缓，这样在保证安全的前提下可以适当提高列车通行速度。