公路修复路堤侵蚀敏感性与边坡稳定性比较

Comparison of Erosion Sensitivity and Slope Stability of Highway Repair Embankment

本研究对比了不同侵蚀控制方法对公路路堤边坡的侵蚀敏感性和稳定性的影响。在边坡0.5~3.0 m不同深度处安装多个张力计,以监测每段边坡内正、负孔隙水压力和渗流情况。通过对5个边坡断面的田间观察,结果表明在降雨量小于1400 mm/年的条件下,以毯层、粗粒土和黏粒土作为控制措施最为有效。当累积降雨量超过3400 mm/年,所有测试路段均出现严重的浅层边坡破坏和地表侵蚀,这种破坏模式与孔隙水压力数据吻合较好。雨季末的孔隙水压力系数r u值为0.40~0.50,当孔隙水压力r u=0.55时,抗剪强度参数c′和φ′分别为10 kPa和40°。

This research compared the influence of different erosion control methods on the erosion sensitivity and stability of highway embankment slope.Multiple tensiometers were installed at different depths of 0.5-3.0 m in the slope to monitor positive and negative pore water pressure and seepage in each slope.Field observations at five slope sections showed that blanket,coarse grained soil and clay soil were the most effective control measures when rainfall was less than 1400 mm/year.When accumulated rainfall exceeded 3400 mm/year,severe shallow slope failure and surface erosion occurred in all tested sections,and the failure pattern was in good agreement with pore water pressure data.The pore water pressure coefficient Ru value at the end of rainy season is 0.40-0.50.When the pore water pressure r u=0.55,the shear strength parameters c′andφ′are 10 kPa and 40°respectively.