水力侵蚀对路基表面稳定性的影响研究

通过降雨试验和天然降雨水土流失调查 ,笔者首先探讨了风化花岗岩地区路基表面水力侵蚀的表现形式和规律 ,其中 ,基床表层已填筑级配碎石的易于发生级配碎石粗粒化 ,未填筑级配碎石的易于发生沟蚀 ;裸露的路堤边坡水力侵蚀发生发展规律一般为 :沟蚀→边坡滑坍 ;裸露的路堑边坡水力侵蚀发生发展规律一般为 :溅蚀→面蚀→沟蚀→坍塌 ;片石护坡的路堤和路堑边坡易于发生潜蚀。然后分析了水力侵蚀对路基表面稳定性的影响 ,认为溅蚀和面蚀对路基表面稳定性的影响较小 ;沟蚀对路堤边坡表面稳定性的影响程度随侵蚀程度和工程进度具体情况而定。最后 ,提出了施工期路基表面防护的建议

Study on Effects of Water Erosion on Stability of Roadbed Surface

By means of artificial rainfall experiments and site investigation of water erosion caused by natural rainfall, the behavior of water erosion on roadbed surface in weathering granite district is discussed The roadbed bedding covered with granular material is more easily to become coarse granules, but the uncovered bedding tends to bring about gully erosion. The development regularities of water erosion on bare road embankment slope and bare cutting slope are gully erosion→shallow slip of slope and splash erosion→surface erosion→gully erosion→collapse respectively. Both the road embankment slope and the cutting slope protected by rag stone are prone to develop subsurface erosion. Effects of water erosion on stability of roadbed surface are analyzed. It is found that splash erosion and surface erosion are rarely happened. The degree of gully erosion influence on stability of embankment surface depends on the erosion degree and engineering schedule. Finally, some suggestions about measures for protecting the roadbed surface during the construction period are put forward.