关键词: V型沟谷, 填方地基, 沉降变形, 渗流分析, 红层泥岩

Abstract: The treatment of airport filled foundation in Southwest China faces increased difficulties due to the superposition effect of unfavorable factors, including V-shaped valley terrain and red-bed mudstone filling material, which may cause foundation settlement deformation and seepage stability problems. Firstly, the law of settlement de鄄 velopment was summarized based on observation data of filled foundation in V-shaped valley. Secondly, a two dimensional planar simulation model was established to simulate the strength attenuation process of red-bed mudstone due to disintegration. Sensitivity analysis was then conducted on the valley foundation parameters. Fi鄄 nally, the effects of rainfall intensity and duration on rainfall-induced seepage were investigated. Research re鄄 sults indicated that an approximately positive correlation existed between fill thickness and post-construction settlement. When the fill thickness increased from 20 m to 40 m, the settlement increased by 77.8%. The lateral constraint of valley can be enhanced with the increase of filling angle; the settlement decreased by 16.8 mm, as the filling angle increased from 10° to 30°. The valley transformed to U-shaped with the increase of base width, which was unfavorable for differential settlement control. Rainfall intensity and duration had a coupling effect on the settlement of the red-bed mudstone foundation, and the maximum settlement increased by 25.7%after 5 consecutive days of rainfall. The research results preliminarily revealed the mechanism of sudden settlement ac鄄 celeration in filled foundation during rainy season.

Key words: V-shapedvalley, filled foundation, settlement deformation, seepage analysis, red-bed mudstone