【作者】 谢贵华；

【导师】 叶晓明；

【作者基本信息】 重庆大学 ， 岩土工程， 2008， 硕士

【摘要】 随着国民经济的快速发展和西部的大开发,铁路、公路、矿山、水利、城市建设等工程出现的填方边坡越来越多,规模越来越大,支护难度越来越高。这些边坡工程的一个共同特点是下滑推力大、支护条件差,用传统的直接边坡支护方法难度大、费用高。这种现状需要迫使研究人员对填方边坡进行系统研究,形成一些新的间接支护方法,以适应填方边坡的快速发展。本文针对填方边坡基底放阶技术其固有的特点进行专门研究。基底放阶技术就是一种在原有诸多滑面改良形式基础上衍生出来的,改良填方边坡稳定性的工程辅助方法。该方法结合直接支挡方法,可形成一种稳定性好、经济合理的填方边坡支挡新技术,改变原有单纯支挡结构的支挡方法,以满足日益严峻的填方边坡形势。本文从填方边坡破坏特点以及主要影响因素研究入手,分析边坡滑移容易从基底面产生的机理。分析出由于水的入渗引起填料中的细粒物质的移动,在填方体下部与稳定基岩之间形成一定厚度的滞水层。该层土体的抗剪强度被弱化,显著低于填料的抗剪强度。基于滞水层存在的分析,建立基底放阶台阶与滑面抗滑参数c、?值之间的计算模型,并提出基底开挖台阶宽度的上、下限控制值计算方法。在此基础上,运用MADIS/GTS有限元程序对填方边坡基底放阶进行了数值模拟分析,主要验证了解析法的正确性并讨论了不同放阶宽度,不同边坡坡比以及不同放阶范围对边坡稳定性的影响。考虑水入渗以及水渗流引起填料中的细粒物质的移动是形成滞水层的前提条件,同时降雨是导致边坡失稳的最主要和最普遍的环境等因素,本文通过考虑降雨渗流与基质吸力作用,针对不同的不同的降雨强度和降雨持续时间对边坡稳定性的影响进行了填方边坡基底放阶渗流-应力耦合分析,验证了在降雨工况下基底放阶法的有效性。最后,结合重庆三汇二矿矸石山工程进行了设计对比,并成功运用于工程实际,取得良好的经济效益。分析表明在提高边坡稳定系数的同时,基地放阶技术具有节约材料,降低施工难度,减少工程造价等特点。基底放阶法台阶计算模型的建立为基底放阶法提供了理论依据,将以前仅作为工程技术处理措施的基底放阶进行量化,成为一种新的设计方法和基底造型技术,具有较大的理论意义和较高的实用价值。更多还原

【Abstract】 With the development of the national economy and west China development drive, There are more and more fill slope engineering of railway, highway, mine, water conservation, and its scale becomes larger and larger, the support of them become more and more difficult. Large gliding thrust force and differential support conditons are characteristic of this kind of slope engineering, and traditional slope supporting method is difficult to manage and expensive.So it is need to do some studies in fill slope, and to explore supporting method to meet the needs of fill slope.In this paper, the inherent characteristics of the fundus ladder technology for fill slope has been specialized studied. The fundus ladder technology is a kind of aiding method to enhance the slope stability, which is derived from many original methods.To integrate supporting method, the new supporting technique of fill slope is formed, which has the features of higher stability and economical construction cost, which has change the original supporting method to meet the needs of the development of fill slope.This paper is based on the wreck features of fill slope and the major factors whic influence the stability of fill slope, and to analyze the cause of land slide along with basal surface. Along with the soil water infiltration to influence the fine grain material infiltration move, the aquitard is formed with certain thickness between filling-up soil and the stable basement. The shear strength of this layer is obviously lower than the filling-up soil. Based on the existence of aquiclude, a calculation model about the fundus ladder of anti-sliding c、? can be built, the control threshold value calculation method of excavation of the fundus steps can be made.On this basis, a numerical simulation of fill slope with MADIS / GTS finite element program is made,which mostly validated the analytics correctly . And stability influence is studied while the fill slope with different step width, inclination angle and the step range.Considering the infiltration and the move of the fine-grained material is the precondition of forming the aquiclude, and rainfall is the most important and general environment of resulting in the slope failure.In this paper, considering the rainfall infiltration and matric suction, according the different duration and strength of rainfall which impact the stability of fill slope, analyzing the fundus ladder method by fluid-mechanical Interaction, some benefit conclusion can be made. Finally, the design contrast is carried on the Chongqing San Hui gangue rocky mountain project, and a good effect is achieved. The analysis has indicated that the fundus ladder technology is economy ,and at the circumstance of assuring stability, Materials was saved, the blasting difficulty was reduced, and the project cost was reduced. It possesses a very good economic benefit.The establishment of calculation model provides a reliable theoretical basis for fundus ladder method. And it became a new method of design and fundus ladder technology. It has the certain theory and the practical value.更多还原