【作者】 雷光宇；

【导师】 谢和平；

【作者基本信息】 中国矿业大学 ， 工程力学， 2009， 博士

【摘要】 伴随着我国大规模经济建设步伐,一个又一个规模宏大的基础设施建设项目在我国建成或即将建成,这些特大型项目的建设极大地改变了我国基础设施落后的局面,促进了国民经济和社会发展,但同时也给生态环境带来一定的负面影响。据调查,三峡大坝建成后,将淹没陆地约632km2,总长5927km的库岸线上将有欠稳定和不稳定的库岸172段共计约385km,前缘高程低于175m的崩滑体约1627处,总体积约38.9亿m3,约占总库容的10%,在这些崩滑体中绝大多数为土质滑坡。变幅达30m的库水位周期性涨落将加剧库区古滑坡的复活,甚至产生新的滑坡,直接威胁库区人民的生命和财产安全。论文以三峡库区某涉水土质滑坡防治工程为背景,针对涉水土质滑坡的稳定性分析和处治技术开展了系统深入的研究,取得的主要成果和创新点有:1)基于非饱和土一维垂直入渗基本理论,研究了经典的Green-Ampt入渗模型和经典的Philip入渗模型,根据这两个模型特征参数之间存在的重要关系,提出了两个模型的改进形式。改进后的入渗模型不仅保留了原模型形式简单、特征参数物理意义明确的优点,同时还克服了原Green-Ampt模型不能表达成时间的显函数、原Philip模型不能确定湿润锋面位置的缺点,更便于工程应用。2)提出了以地表理论积水时间、地表实际积水时间和地表平均积水深度为重要参数的求解降雨入渗问题的改进的Green-Ampt模型和改进的Philip模型,运用这两个模型计算了三峡库区某涉水土质滑坡在极端降雨量时滑体土的饱和浸润深度。计算结果表明:在降雨量不变的情况下,短时间暴雨造成的入渗浸润深度明显小于长时间小雨造成的入渗浸润深度。当降雨强度小于土壤饱和入渗率时,入渗浸润深度主要受降雨总量和雨前土壤初始含水量控制。3)基于潜水一维流Dupuit假定,通过引入含水层平均厚度,对Boussinesq非线性方程做线性化处理,得到了具有不规则隔水底板和不规则岸坡的坡体在库水位等速涨落时坡体内地下水浸润线的近似解析解。提出了不同于传统抛物线浸润模型的新抛物线浸润模型,提出了既考虑时间区段变化又考虑空间区域变化的含水层平均厚度计算方法,从理论上论证了传统方法局限性。4)运用大型有限元软件ABAQUS模拟了库区典型滑体土在持续降雨、库水位等速涨落单独作用以及持续降雨与库水位等速下降联合作用下地下水渗流场的动态变化过程,得到了不同降雨强度、不同降雨持时、不同隔水底板倾角、不同库水涨落高度时地下水浸润线的变化规律。5)基于传递系数法,针对涉水土质滑坡稳定性分析,提出了以滑动面特征点、浸润线相交点为节点将计算剖面垂直分条,用降雨饱和区、非饱和区、潜水饱和区将计算条块分区的新条分方法,并相应地确定了计算条块各分区所受重力和渗透力的计算原则。工程算例表明,该方法概念清楚,计算简便,克服了长期以来凭经验考虑降雨入渗对滑坡稳定性影响的盲目做法,特别适合工程应用。6)采用地表截排水、抗滑桩阻滑、重力式挡墙支挡、挡板护岸等处治技术综合治理三峡库区某涉水土质滑坡,成功地阻止了滑坡灾害的继续发展,两年的监测数据说明,该滑坡的处治措施合理有效,达到了预期的治理效果。更多还原

【Abstract】 With the step of the large-scale economic development of our country, most of the infrastructure construction item in our country has been finished or will soon be finished, these extra-huge construction item changed the lag situation in our country, helped the national economy and the social development ,at the same time given the negative effect to the ecological environment. According to the survey, the land about 632 km2 would be submerged after the Three Gorges dam been built up. There are 172 non-stable reservoir bank along with the reservoir bankline which about 5927km, add up to 385 km, the elevation lower than 175m in front of the sub-slides has 1627, the volume accumulates about 3,890,000,000 m3, has a probation of 10% of the total reservoir volume, for the most part is soil landslide in there slump-mass. With the reservoir water which has a variability of 30m rise and drop periodically the revival of the ancient landslide would be accelerated. Maybe a new landslide would be produced, threaten the security of this region directly.Thesis take one hydrous slope for example, carried a study about stable analysis of the hydrous slope deeply. The main achievement and innovation have:(1) Thesis take one-dimensional vertical infiltration of not-saturated soil as basic theory, studied the Green-Ampt and the Philip model. Some characteristic parameters of these two models have relationship. So thesis put forward new models to improve. The infiltration model after improved not only reserved the advantage of original models, but also overcome the disadvantage, become easier to apply for engineering.(2) Thesis put forward some new parameter to carry out the seepage problem, made use of these improved models to compute the saturated infiltration of landslide in the extreme-rainfall condition. Compute result shows that: At the condition of unchanged rainfall, the infiltrating depth by short-time rain smaller than long-time’s. The infiltrating depth controlled by rainfall and moisture content mainly when rainfall smaller than saturated infiltration.(3) Thesis take Dupuit suppose as basic theory, convert Boussinesq equation into line one by added average thickness of moisture content , the approximate solution of groundwater saturation line was obtained when the water table rise and drop along the random water-resisting floor and slide. Put forward new parabolic liquid wetting property and compute method. It proved the limitations of traditional methods theoretically.(4) Thesis use ABAQUS software to imitate dynamic change of groundwater seepage field in the effect of rainfall and water table. The change regulation of groundwater saturation line with different rainfall, gradient and water table was obtained.(5) Thesis carried in stable analysis of hydrous slope by use of modulus method. Put forward new slice method and compute order. Engineering calculates shows that the method is clear and simple, overcome the disadvantage of empirical method, easier to apply for engineering.(6) Treatment technique of someone waded soil landslide project in this paper succeeded in preventing the continued development of the landslide hazard by use of surface cut-drainage, anti-skid anti-slide pile of reinforced concrete, gravity-type retaining wall bracing and baffle-revetment of inter-pile reinforced concrete. Monitoring data shows that the landslide control project in Treatment measures are reasonable and effective governance to achieve the desired results on two years.更多还原