Waterproofing and Drainage System Design of YUN-GUI Express Railway Cutting Sub-Grade in Expansive Soil Area

According to the character and generation mechanism of railway cutting sub-grade diseases, following the needs of YUN-GUI express railway construction, based on the results of laboratory and field test of expansive soil engineering characteristics, developed new waterproof material, designed waterproofing and drainage system of cutting sub-grade, and full-scale dynamic model test was carrying out, a cycle load with 4Hz frequency and 4000 thousand times excitation was imposed on the sub-grade model under three kinds of working condition (dry, raining and underground water rising). The results indicate that: no cracks appeared on the surface of semi-rigid waterproof layer, its durability is good. Waterproofing and drainage system of cutting sub-grade works well under combined action of long term cycle load and complicated environment. Research results possess important engineering reference value.