CAJ | 학술논문

针对坡角为70°的黄土边坡，进行2.7 mm/min降雨强度下的室内坡面冲刷试验。根据边坡冲刷破坏的过程特征，将边坡侵蚀方式演变过程归纳为试验初期的片蚀、中期的细沟侵蚀、到后期的切沟侵蚀和坍塌。试验中坡顶处侵蚀强度大于其他部位，当坡面形成上下贯通的切沟之后，水流开始掏蚀沟槽底部土体，随着冲刷的持续，切沟两侧土体强度降低，坡顶土体发生坍塌。以此为基础利用三维颗粒流软件 PFC3D对边坡降雨冲刷过程进行流-固耦合模拟，在模拟颗粒大变形的同时得到颗粒运动轨迹、孔隙率、流体单元内流速等重要参数，这些参数的定量变化过程反映了降雨过程中边坡遭受侵蚀程度及水流侵蚀能力的分布规律：坡顶处侵蚀最为强烈、水流侵蚀能力最强，且两者随高度降低呈减小趋势，与室内试验结果一致。
침대파각위70°적황토변파，진행2.7 mm/min강우강도하적실내파면충쇄시험。근거변파충쇄파배적과정특정，장변파침식방식연변과정귀납위시험초기적편식、중기적세구침식、도후기적절구침식화담탑。시험중파정처침식강도대우기타부위，당파면형성상하관통적절구지후，수류개시도식구조저부토체，수착충쇄적지속，절구량측토체강도강저，파정토체발생담탑。이차위기출이용삼유과립류연건 PFC3D대변파강우충쇄과정진행류-고우합모의，재모의과립대변형적동시득도과립운동궤적、공극솔、류체단원내류속등중요삼수，저사삼수적정량변화과정반영료강우과정중변파조수침식정도급수류침식능력적분포규률：파정처침식최위강렬、수류침식능력최강，차량자수고도강저정감소추세，여실내시험결과일치。
A series of experiments of slope rainfall erosion were done in laboratory for steep loess slope with slope angle of 70° under a rainfall intensity of 2.7 mm/min. According to the characteristics of slope erosion, the evolution of rainfall erosion process is generally concluded as splash and sheet erosion in earlier phase, rill erosion in middle phase, and finally evolved into gully erosion and collapse in later phase. It was found that the degree of erosion at the slope top is stronger than other positions during the experiment;after a through gully formed on the slope surface, the water flow then began to scour soil inside the gully;with rainfall lasting, the strength of the soil around the gully obviously decreased;consequently collapse took place at the slope top and eventually caused wholly demolition of the slope. Based on the experiment, simulating the slope erosion process with PFC3D with fluid-soil coupling method, observing the large deformation of particles, simultaneously the microcosmic parameters such as particle motion trace, porosity and water flow rate in fluid cells are obtained; from their quantitative change process, the distribution of degree of erosion and erosion intensity of water flow in slope is got;it indicated that the degree of erosion and the erosion intensity of water flow at slope top are strongest and both reduced as the height decrease, which is consistent with the indoor model experiment.