高速铁路论文：软弱土地基盾构隧道高速列车动力响应分析.doc

高速铁路论文：软弱土地基盾构隧道高速列车动力响应分析【中文摘要】近年来高速铁路在世界范围内广泛发展,我国的高铁建设发展迅猛,高铁技术逐渐成熟,但与此同时铁路交通振动引发的问题凸现出来。为了服务于经济发展,高速铁路需连接各经济发达的地区,多数必经过长江三角洲、珠江三角洲等地区,铁路隧道多修建在深厚的饱和软粘土、松散砂土等软弱地基中。在高铁列车振动荷载反复的激扰下,孔隙水压力骤升,周围的粘土阻断排水,孔隙水压力难以弥散,最终液化失去抗剪强度,导致隧道沉降,影响立车行驶的平稳程度,轻则影响旅客乘车舒适度,重则影响行车安全。本文将列车振动和砂土液化相结合进行了分析和计算。首先,以地铁列车振动研究为基础,讨论列车振动荷载的机理,选取人工数定激励力施加在以Euler梁模拟的轨道上,计算得到无砟轨道承轨台支反力,然后,将支反力施加到隧道-围岩模型上进行计算。计算中结合饱和土动力固结理论,采用Finn-Seed模式,进行了在高速列车动荷载激扰下的水-土二相流固耦合分析。分别分析了均匀地层中盾构隧道的动力响应,以及地应力和孔隙水压力分布规律；长期重复列车何在作用下,隧道结构的动力响应规律,以及地应力的变化规律和孔隙水压力的集聚和弥散规律。【英文摘要】While the technology of high-speed railway gradually approaching mature under the circumstance of high-speed railway developing globally and soar development of high-speed railway construction in domain, the problem caused by vibration of railway communication became prominent. For serving economy growth by connecting the major cities located in Yangtze River delta, Pearl River delta and etc, railway tunnels frequently embedded in thick soft soil as saturated clay or unconsolidated sand. Exposed to train vibration excitation, pore pressure suddenly soar and dissipation delayed due to blocked drainage of surrounding clay, which finally lead to liquefaction and shear strength loss, tunnel subsidence, infected smoothly running and comfort of passenger even the safety of railway transportation.The analysis of this dissertation combined the train vibration and sand liquefaction. First, discussing mechanism of high-speed train vibration based on reviewing relevant subway research, artificially numbered excitation force is applied to the track simulated as unlimited Euler-Bernoulli beam to gain the reaction force of track supporting platform of ballastless track structure via calculation. Then this force is exerted to tunnel-ground model to calculated analysis. Combining dynamic consolidation theory of saturated soil and using Finn-Seed model, according to fluid-solid coupling situation of water-soil undergoing vibration induced by high-speed train, this dissertation respectively analyzeddynamic response of shielded tunnel and the feature of ground stress and pore press distribution;dynamic response of tunnel structure, variation of stress field and the stimulation and diffusion of pore pressure tolerating long-term cyclic high-speed train load.【关键词】高速铁路 隧道结构 列车振动 砂土液化 动力分析【英文关键词】high-speed railway tunnel structure train vibration sand liquefaction dynamic analysis【目录】软弱土地基盾构隧道高速列车动力响应分析摘要6-7ABSTRACT7第1章 绪论10-241.1 引言10-121.2 国内外研究现状12-181.2.1 列车振动的产生机理及荷载模拟12-141.2.2 列车振动传播与隔减振的研究14-151.2.3 分析列车振动问题的数值计算方法15-171.2.4 砂土振动液化和振陷的研究17-181.3 课题的工程背景18-191.4 现有的问题和待研究的方面19-201.5 本文的研究内容及意义20-24第2章 列车荷载的确定方法24-352.1 列车振动荷载形成的机理24-272.1.1 轮对因素导致振动的机理24-262.1.2 轨道不平顺因素26-272.2 高速列车激振27-302.2.1 人工数定激励力28-292.2.2 列车轨道系统模型29-302.3 无砟轨道高速列车振动荷载30-342.3.1 无砟轨道弹性地基模型31-332.3.2 动力荷载的确定和施加33-342.4 小结34-35第3章 流固耦合动力分析的本构模型及边界条件35-493.1 流固耦合分析基本理论35-403.1.1 饱和土动力固结理论35-363.1.2 流固耦合计算原理36-403.2 本构模型40-443.2.1 Mohr-Coulomb屈服准则41-423.2.2 Finn-Seed模式及Byrne模式42-443.3 动力分析边界条件44-453.3.1 人工边界44-453.3.2 材料阻尼453.4 砂土液化机理及判别准则45-473.4.1 砂土液化机理45-463.4.2 判别准则46-473.5 小结47-49第4章 均匀地层下盾构隧道的动力响应49-654.1 构建模型49-504.1.1 计算范围494.1.2 本构关系49-504.1.3 边界条件及阻尼参数504.2 地层位移及速度响应分析50-554.2.1 地层位移分布规律51-524.2.2 速度分布规律52-534.2.3 管片环位移变化规律53-554.3 动力响应时程分析55-614.3.1 管片环位移时程分析56-584.3.2 地层位移响应分析58-614.4 地应力及孔隙水压力分析61-634.4.1 地应力响应分析61-624.4.2 孔隙水压力变化规律62-634.5 小结63-65第5章 列车振动饱和砂土动力响应及长期振动特性65-965.1 构建模型65-675.1.1 本构模型65-665.1.2 计算范围66-675.1.3 边界条件及阻尼参数675.2 地层位移及速度响应分析67-755.2.1 地层位移分布规律68-705.2.2 速度分布规律70-725.2.3 管片环位移变化规律72-755.3 动力响应时程分析75-815.3.1 管片环位移时程分析76-785.3.2 地层位移响应的分布规律78-815.4 地层应力及孔隙水压力分析81-875.4.1 地层应力响应分布规律81-825.4.2 地层孔隙水压力积聚及弥散规律82-865.4.3 地层孔压比变化规律分析86-875.5 列车重复作用