Infiltrating properties of modified swelling soil subgrade

The physical properties, mineral composition and expansive-shrinkage characteristics of the borrow soil were studied, and the evaluation of expansive potential was carried out. The influence of lime-swelling soil by rainfall was analyzed. The results show that the expansion and shrinkage change obviously, the compaction degree lowers clearly and the strong expansive appears where the soil compaction is high. 90 days later, the subgrade deflection becomes stable, and reaches the required strength. As for the subgrade filled with improved light or mid lime-swelling soil, the influence of rainfall appears during the early days of the filled subgrade, and its strength will recovers continuously while the water content lowers naturally. 9 tabs, 5 refs.