| 摘要: |
| 本次试验以厚层砂土型河道岸坡为对象，研究不同降雨强度和岸坡坡比下的砂土岸坡变形破坏过程。共设计五组室内物理模型试验，每组试验均埋设水分计、微型孔压计、引线式温度计测量，并利用高精度摄像机记录岸坡变形破坏的全过程。试验结果显示：抗剪强度试验表明非饱和砂土黏聚力随含水率增大，呈现出先增大后减小的趋势，并具有明显的峰值，内摩擦角呈现随含水率增大而减小的趋势；不同雨强及不同坡比情况下，砂土岸坡的变形破坏表现为两种不同的机制；短历时降雨会在坡体表层形成饱和区，阻止雨水的入渗，砂土层不同深度水分运移各异，雨水的入渗路径并非单一的垂直入渗；岸坡侵蚀破坏是在雨水冲刷、降雨入渗以及重力侵蚀的耦合作用下发生的。 |
| 关键词: 砂土岸坡 降雨冲刷 物理模型试验 变形破坏 |
| DOI： |
| 分类号:TU411 |
| 基金项目:国家自然科学基金面上项目（51979174)，国家自然科学基金长江水科学联合基金项目（U2240221） |
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| Experimental Study on Physical Model of The Bank Slope of Thick Sandy Soil Under Rainfall |
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WU Bing1, ZHANG Guirong2, CHI cheng3, KONG yang2, LI denghua2, DING Yong1
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1.School of Science,Nanjing University of Science and Technology,Nan’jing;2.Nanjing Hydraulic Research Institute,Nan’jing;3.College of Water Conservancy and Hydropower Engineering,Hohai University,Nan’jing
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| Abstract: |
| In this experiment, the bank slope of the thick sandy soil type was taken as the object to study the deformation and failure process of the sandy soil bank slope under different rainfall intensities and bank slope ratios. A total of five groups of indoor physical model tests are designed. Each group of tests is embedded with moisture meter, micro porosimeter, and lead-type thermometer. High-precision cameras are used to record the entire process of bank slope deformation and failure. The test results show that the shear strength test shows that the cohesion of unsaturated sand increases with the increase of water content, showing a trend of first increase and then decrease, and has an obvious peak value, and the internal friction angle decreases with the increase of water content. There are two different mechanisms for the deformation and failure of sandy soil bank slopes under different rainfall intensities and different slope ratios; The surface layer forms a saturated zone to prevent the infiltration of rainwater. The water migration of different depths of the sandy soil layer is different. The infiltration path of rainwater is not a single vertical infiltration; occurs under the coupling effect. |
| Key words: sand bank slope rainfall erosion physical model test deformation failure |
