【作者】 王涛；

【导师】 姜忻良；

【作者基本信息】 天津大学 ， 结构工程， 2007， 硕士

【摘要】 在城市地铁工程的修建中,盾构法隧道施工技术以其独有的智能化、安全、快捷等特点与优势,越来越得到广泛的推广和应用。盾构法己成为我国城市地铁施工中一种重要的施工方法。虽然盾构法取得了斐然成绩,但此法施工不可避免地引起地表沉降,地表沉降过大时,会影响到盾构隧道的安全施工和地表建筑物的正常使用。由施工引起的地面沉降及其对周围环境的影响是盾构隧道设计和施工中非常关心的问题。有限元法是计算盾构隧道开挖的重要方法。本文从数学与力学研究方法入手,开展了盾构施工引起土体变形的三维有限元数值计算的研究;根据工程实际,综合考虑盾构隧道施工过程中的材料非线性、盾尾建筑空隙、盾构密封舱内土压力、土体与衬砌结构的相互作用等因素,利用有限元方法对盾构隧道动态开挖过程进行模拟。本文以天津地铁某区间盾构施工为背景,建立了盾构法隧道施工的三维有限元分析模型,针对近距离双线平行的多种工况采用ABAQUS程序进行了数值模拟分析,揭示了在盾构新隧道施工时对既有隧道产生的影响,包括地表沉降、老隧道的应力分布和衬砌变形等。结果表明,土体的模量、隧道间净距、注浆压力等因素对隧道间相互作用有较大影响,且土体越软其影响越显著,应在工程中引起足够的重视。更多还原

【Abstract】 Tunnel construction technology with shield driven method is being more and more developed and applied in building Metro engineering because of its’ unique characteristics and advantages such as intelligence, safety and quickness, etc. The shield driving method has been one of the main construction methods in the metro engineering of our country. Though shield driven method has obtained splendid achievements, it is inevitably caused ground surface settlement. This will affect the normal use and the safe running of the shield tunnel and the ground surface building while the ground surface settlement is too much.The surface settlements and influence on surrounding environment caused by shield tunnelling are the problems highly concerned in the design and construction process of shield tunnel.The finite element method is the main method of tunnel excavating. In this paper, three-dimensional Finite Element Method is applied to study the ground deformation by shield driven. According to the real engineering, the author bring forward a 3D model to simulate the tunnel excavating by means of the finite element method. The key factors such as the soil conditions of Tianjin area, the nonlinearity of soil material and the structure void of shield and the interaction between the gasket and soil also been taken into account in this 3D model.Based on a subway project in Tianjin, three-dimensional finite element analysis is carried out to simulate double-tube parallel tunnels with short distance between them. In this paper ABAQUS is used to analyze several projects. The laws of influence on the old tunnel and ground face settlement caused by the construction of the new tunnel are obtained. The results show that the modulus of soil and the net distance between the tunnels and the grouting pressure have great influence on the interaction. The softer the soil is, the more severe the influence is, which should be considered in projects.更多还原