【作者】 林源；

【导师】 胡长明；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2011， 硕士

【摘要】 论文以西安市地铁一号线通化门车站深基坑工程为实际背景,运用理论分析、现场监测、室内试验和有限元数值模拟相结合的研究方法,对黄土深基坑开挖所引起的环境效应开展了相关研究。首先,根据工程实际情况,制定切实可行的现场监测方案,对深基坑开挖的整个施工过程进行现场实时监测,并对部分监测数据进行分析与处理,得到各开挖阶段围护桩的水平位移、钢支撑轴力、周边建筑物及地面沉降所对应的变化规律。其次,以有限元软件MIDAS/GTS为计算工具,对基坑及其周边建筑物建立了三维的有限元模型,主要研究了以下内容:基于现场监测数据,并结合室内岩土力学试验确定的土层材料的有关力学参数,建立了基于摩尔-库仑屈服准则的基坑动态施工开挖的有限元计算模型,从中获得支护体系的内力和变形规律、基坑周边地面及建筑物的沉降变化规律,并将计算结果与监测结果进行对比分析,寻找与总结黄土深基坑变形的预测方法;借鉴国外隧道施工规范,建立了深基坑施工对周边建筑物影响的损害评价系统。最后,运用室内试验的方法检验了袖阀管注浆改良黄土土层的效果,并借助现场实测和数值模拟相结合的办法,从基坑整体稳定性、立交桥桩水平变形、实测桥桩沉降等方面,对基坑东端头桥桩下袖阀管注浆加固的效果进行了评价。论文的研究成果对该工程的相关设计和施工,以及今后类似工程的修建具有重要的指导意义。更多还原

【Abstract】 In this paper, based on Xi’an No. 1 subway line of Tonghua Gate station, the environmental effect of deep foundation excavation in loess region is studied by the means of theoretical analysis, site monitoring, laboratory test and FEA numerical simulation.First, according to the truth of the project, the feasible site monitoring scheme is formulated to monitor the construction process. And some of monitoring data is analyzed and processed to obtain the horizontal displacement of the guard posts, steel support axial force, settlement changes of surrounding structure and the ground at different excavation stages.Second, three dimensional finite element models are built through element analysis software MIDAS/GTS. Based on site monitoring data and indoor rock-soil mechanics test to determine mechanical parameters of the soil materials, the finite element model is built to gain the internal force and deformation regulation of the supporting system and the settlement regulation of the surrounding structure and the ground. Then the forecast method of the loess deep foundation deformation is summarized with the comparison of the calculation and monitoring results. Reference to foreign tunnel construction standard, the damage evaluation system of the influence that the deep foundation has on surrounding structure is built.Last, the effect of using sleeve valve barrel grouting to improve loess soil is checked by the means of laboratory test. And with the help of site monitoring results and numerical simulation, the effect of sleeve valve barrel grouting reinforcement, which is using in the neighbor bridge pile of foundation, is estimated from improving the overall stability of the foundation pit, controlling horizontal displacement of the bridge pile and measuring bridge pier settlement. The research achievement of the paper plays an important role in conducting the design and construction of this project and the similar project.更多还原