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以龚家方、茅坪、神女溪岸坡为例,总结了三峡库区类土质岸坡蓄水解体演化的5个阶段:岸坡形成阶段、节理裂隙发育阶段、泥化夹层及类土质岸坡形成阶段、蓄水作用岸坡解体阶段以及后续解体阶段。根据上述演化过程,从断裂力学角度建立了类土质岸坡解体的物理模型和力学模型,该力学模型考虑了5种蓄水工况下的受力状态,推导了相应的应力表达式和断裂强度因子公式。初步探讨得出以下结论:水库蓄水对类土质岸坡解体影响较为显著,岩块断裂强度因子随着蓄水位的升高而不断递减,蓄水水位升至4.49 m时,岩块断裂趋势由上部断裂转为下部断裂,断裂强度因子随着水位增高而增大。蓄水伊始,岩块重力对断裂起主要作用,而水位抬升起到一定的稳定作用;水位继续抬升,由重力主导的上部断裂逐渐转化为由浮托力决定的下部断裂。岩块的截面尺寸对类土质岸坡解体具有重要的影响。当岩块上部断裂时,断裂强度因子随着宽高比的减小而增加;当岩块下部断裂时,随着宽高比的减小,岩块断裂强度因子随蓄水位的增加而增大。
Taking Gongjiafang, Maupin and Goddess Creek banks as an example, the paper summarizes five stages of the evolution of soil-like bank slope in the Three Gorges Reservoir area: the formation of bank slope, the development stage of jointing and fissuring, the formation of muddy intercalation and soil-like bank slope Stage, the role of water storage slope bank disintegration stage and the subsequent disintegration stage. According to the above evolution process, the physical model and mechanical model of soil-like bank slope disintegration are established from the point of view of fracture mechanics. The mechanical model considers the stress state under five kinds of storage conditions and deduces the corresponding stress expression and fracture strength Factor formula. The preliminary conclusions of the study are as follows: The impact of reservoir water storage on the collapse of soil-like bank is significant, and the fracture strength of rock mass decreases with the increase of water level. When the water level rises to 4.49 m, From the upper fracture to the lower fracture, the fracture strength factor increases with the increase of the water level. At the beginning of water storage, the gravity of the rock mass plays a major role in the fracture, while the water level rise plays a stabilizing role. The water level continues to rise and the gravity-dominated upper fault gradually transforms into the lower fault determined by the floating force. The section size of the rock mass has an important influence on the dissolution of the soil bank. When the upper part of the rock mass is broken, the fracture strength factor increases as the aspect ratio decreases. When the lower rock mass is broken, the fracture strength factor of the rock mass increases with the increase of water level as the aspect ratio decreases Big.