【作者】 朱向东；

【导师】 尚岳全；

【作者基本信息】 浙江大学 ， 防灾减灾工程及防护工程， 2007， 硕士

【摘要】 官家滑坡是一个典型的碎石土滑坡，这类滑坡在我国南方地区广泛发育，地下水是影响碎石土边坡变形和稳定性的重要因素。随着山区工程活动的增加，碎石土边坡变形及稳定性问题大量出现。碎石土滑坡的变形破坏具有缓慢发育和多次复发的特点，本文结合官家滑坡坡脚开挖失稳破坏过程，在现场调查和理论分析的基础上，提出具有针对性和实用性的碎石土滑坡防治对策。地下水对土体的渗流作用是通过作用在土颗粒上的渗透力产生的。由渗透力的公式推导过程及结果可知：单位面积的渗透力只与渗透坡降有关。通过现场调查和试验资料分析发现，坡脚开挖导致边坡管网渗流系统的破坏失效，会引起渗流场和应力场的改变。本文采用饱水面积比衰减强度参数对水位上升的影响进行量化分析，提出改进的传递系数法，通过实例分析表明该方法能更准确地描述滑坡稳定状态；当地下水位降低时，会产生对滑坡稳定不利的渗透力，渗流作用下渗透力产生的同时会导致下滑力增加，对边坡稳定性造成负面影响。通过考虑渗流作用下和不考虑渗流作用下边坡稳定性有限元计算对比分析，评价渗流对边坡稳定性的影响，并对不同渗透系数进行边坡稳定性计算和有限元分析。碎石土边坡的变形破坏和复发失稳主要是由地下水渗流场在强降雨和连续降雨的触发下发生变化所引起，结合滑坡变形破坏的因素敏感性分析，针对目前滑坡防治工作中存在的问题，提出以治水为主的碎石土滑坡防治策略。更多还原

【Abstract】 Guanjia landslide is a typical debris landslide, which developed widespread in southern of china.Groundwater is one of the most significant factors affecting the deformation and the stability of slope. Pipe drainage of groundwater is often developed in the debris slopes in Zhejiang province and is important in restricting groundwater level rising and in keeping slope stability. Cutting at slope toe or loading on slope surface may destroy the pipe seepage system and make groundwater level rise obviously. As a result, the pore water pressure on a potential slip surface will rise and a landslide may take place. The deformation and failure of debris landslide is a slow-developing process and may re-collapse. Based on the field investigation and theory analysis, the paper has presented the practical and usefully treatment for debris landslide.The influence of the groundwater seepage on soil mass comes to be true through the seepage force on the soil grain. According to the formula of the seepage force, it can be deduced that the seepage force only lies on the hydraulic gradient. The sections of different utilization degrees of share strength are determined by saturation-area ratio. Based on it, improved transport coefficient method is presented which can more reflect actual locating state of debris landslide. After the first deformation, a new pipe drainage system will establish. Then, water level depression will generate seepage force which is disadvantage for the stability of slope. The downslide force can be increased with the seepage force in slope mass as the seepage, which has a bad effect on the stability of slope. The paper simulates the stability of slope considering the seepage and without it by the finite element software and evaluates quantificationally the effect degree of the seepage on the stability of slope.Rainfall is the main induced factor for deformation and recollapse of debris slope. Focusing on the problems in the present landslide treatment measures and combining with sensitivity analysis on destroy mechanism of debris slope; a new control strategy is presented that is the drainage of groundwater shall be the major measure to increase thestability of debris landslide.更多还原