【作者】 李杰；

【导师】 余振锡；

【作者基本信息】 安徽工业大学 ， 市政工程， 2018， 硕士

【摘要】 双排桩-锚索支护结构是一种比较新颖的支护形式,其结合了双排桩与桩锚支护的技术优势,并将其结合成为一个整体。目前对该支护结构的研究较少,现场实测资料比较匮乏,存在着理论远远滞后于实际应用;其有限元分析大多都是按照二维模型进行分析,未考虑其空间效应,具有一定的局限性。本文在双排桩和桩锚支护结构常用计算方法的基础上,对双排桩-锚索支护结构进行了受力计算;以马鞍山综合客运中心枢纽站采用双排桩-锚索支护形式的基坑工程为依托,运用ABAQUS有限元数值模拟软件创建该支护结构的三维数值模型,按照现场基坑分步开挖与支护的工序进行数值模拟,分析前、后排桩的受力与变形,主要研究成果如下:(1)简要总结双排桩与桩锚支护结构的国内外研究现状,指出双排桩-锚索支护结构在研究方面目前存在的问题;(2)通过类比双排桩、桩锚支护结构常用计算方法,由此提出双排桩-锚索支护结构的计算模型,并用理正深基坑7.0软件验证其计算结果的合理性。(3)本文以马鞍山综合客运中心枢纽站基坑工程为依托,应用ABAQUS对该工程进行模拟,详细分析在双排桩-锚索支护条件下,该基坑在不同工况下土体的水平侧移、土体沉降与隆起、双排桩的变形问题。并通过对现场监测数据分析来验证数值模拟结果的合理性。(4)通过改变双排桩桩径、桩间距、锚索预应力、锚索倾角等影响因素,分析前、后排桩的水平位移和弯矩变化规律,以此优化双排桩-锚索支护设计。更多还原

【Abstract】 The double-row pile-cable supporting structure which takes the technical advantages of double-row piles and pile-anchor supports and commendably combines the two supports into a whole is a relatively novel form of supports.However,to date,there is still a lack of researches on this supporting structures and the data of actual measurement on the spot is critically deficient.In such case,the theory of the double-row pile-cable supporting structure is far behind the demand of the actual application.The finite element analysis is mostly based on two-dimensional model without considering the spatial effects,so it has certain limitations.In this study,the stress of the double-row pile-anchor supporting structure is analyzed and calculated on the basis of the common calculation methods of double-row piles and pile-anchor supporting structures.The commercial software ABAQUS is used to create a three-dimensional numerical model of the support structure that is based on the form of foundation pit engineering adopted for the Maanshan integrated passenger transport center hub station.And according to the process of excavation and support in the foundation pit,the mechanical analysis of the front and rear row piles is conducted.The main research results are as follows:(1)The status of domestic and foreign researches on double-row piles and pile-anchor retaining structures is briefly summarized,and the current problems in the research of double-row pile-anchor support structures is pointed out;(2)A calculation model of the double-row pile-anchor support structure is proposed by analogy with the calculation method of double-row piles with pile-anchor retaining structures and the rationality of the calculation results are verified with Lizheng deep foundation pit 7.0 software.(3)ABAQUS software is used to simulate the practical project of the foundation pit engineering of Maanshan integrated passenger transport center hub station project in this study.And the lateral movement of soil,soil settlement and uplift and deformation of the double row pile on different working condition under double-row pile-anchor support are detailedly analyzed.The feasibility of numerical simulation results are verified through the analysis of on-site monitoring data.(4)Double-row pile diameter,pile spacing,anchor prestress,and anchor cable inclination angle are selected as the influence factors to analyze the horizontal displacement and bending moment variation law of the front and rear row piles andthe results may provide guidelines to optimize the design of the double-row pile-cable support.更多还原