季节性冰冻地区公路边坡侵蚀破坏模式

针对季节性冰冻地区的路基边坡冻融滑坍破坏现象，分析了公路边坡破坏的各种侵蚀模式和影响因素。采用坡面流拖曳力法、坡面流量法等对坡面水力学特征进行研究，测算坡面冲刷临界坡度值，分析临界坡度与冲刷量之间的关系；同时采用有效应力法研究了冻融作用下的边坡安全稳定性。结果表明：季节性冰冻地区粘性土最大冲刷强度对应的临界坡度与目前常用的坡度值很接近或交叉，为减少水土流失，建议放缓土质边坡；边坡土体冻结前含水质量分数和融化后抗剪强度下降幅度是影响冻融滑坍破坏的主要因素，建议在设计中要考虑冲刷和冻融因素，并对特殊土质边坡进行相应的物理力学指标检测和稳定性验算。

Erosion collapse mode of highway slope in seasonal frost area

The present state of highway slope collapse in north-east of China is serious in early spring due to repeating freezing-thawing effect. The different modes and influencing factors of the collapse are analyzed, the hydro mechanical characteristic of slope is studied with slope drag force method and slope flow method, the critical gradient for erosion of the slope is measured, the relation of critical gradient with erosion is presented, the safety and stability of slope after freezing-thawing is checked by effective stress method. The results show that the critical gradient value of clay in north-east of China is near or cross over the safe value common used in highway at present, so the gradient of soil slope should be decreased to reduce soil-water loss; the main factors influencing freezing-thawing collapse are water content in soil slope before freezing, the scope of shear strength should be declined after thawing. In practical project design, the influencing factors include wash-off and freeze-thaw destroy should be considered, and the test of physical mechanical indexes and the stabilization checking should be carried out. 3 figs, 9 refs.