强降雨作用下黄土陡坡开裂特性测试

降雨诱发黄土边坡失稳具有严重的破坏性。为了研究强降雨条件下黄土陡坡的开裂特性，在陕北吴起开展了黄土陡坡现场人工模拟中雨和大雨试验，分析了坡体含水率及土压力响应，总结了边坡开裂特征、开裂模式及土工布隔离槽的工程效应。研究结果表明：24 h中雨条件下黄土陡坡含水率和土压力上升幅度有限，而144 h大雨条件下边坡表层形成较大厚度的临近饱和区且表层土压力增长明显；144 h大雨条件下黄土陡坡的破坏顺序为坡顶开裂—坡面鼓胀—局部滑动贯通，并且坡顶开裂具有易发性和先导性；边坡破坏模式为自坡顶至坡面的贯通浅层破坏。

Experimental Study on Cracking Characteristics of Loess Steep Slope Under Intensive Rainfall

Instability of loess slopes induced by rainfall is severely destructive. In order to study the cracking characteristics of loess steep slopes under intensive rainfall, the field artificially simulated moderate rain and heave rain tests of loess steep slopes were carried out in Wuqi, northern Shaanxi Province. The water content and earth pressure of slopes were analyzed, along with their cracking characteristics and cracking patterns. The engineering effects of geotextile isolation grooves were summarized. The results showed that the rise of water content and earth pressure of the loess steep slope was little after 24 h moderate rain; While a thicker adjacent saturated zone was formed on the surface after 144 h heave rain, and the earth pressure increased significantly. The main failure sequence of the loess steep slope under the condition of 144 h heavy rain was top cracking, surface bulging, and local sliding in. The top crack of the slope is a precursor, and the failure mode of the slope is a shallow failure from the top to the surface of the slope.