复杂条件下的地铁盾构隧道的力学行为研究  

Study on Mechanical Behavior of Metro Shield Tunnel under Complex Conditions

作　　者：李春良[1,2] 王方彦 张立辉[1] 王静[1] 

机构地区：[1]吉林建筑大学交通科学与工程学院,吉林长春130118 [2]吉林大学交通学院,吉林长春130022

出　　处：《铁道学报》2016年第5期103-109,共7页Journal of the China Railway Society

基　　金：国家自然科学基金(51308256);住房和城乡建设部科学技术计划(2014-K1-066);吉林省教育厅"十二五"科学技术研究项目(2015265)

摘　　要：为研究复杂条件下运营地铁盾构隧道的纵向力学行为,基于双参数弹性地基理论,引入状态空间理论思想,建立了地铁盾构隧道的纵向力学模型,该模型可在考虑土体剪切变形情况下,研究纵向具有不同刚度的盾构隧道穿越复杂土层时的内力与变形规律。计算结果表明:当盾构隧道由硬土层进入软土层后,盾构隧道的受力与变形发生突变,力学性能下降,位于软、硬交接面处的隧道截面最易发生破坏。可通过提高软土层内盾构隧道的纵向刚度值,来抵消盾构隧道进入软土区出现的过大的沉降变形问题;当盾构隧道损伤或被加固后,盾构隧道的纵向内力发生重分布,并且局部刚度损伤度越大,盾构隧道在此处的挠度、转角的增量也越大,同时损伤段内出现内力卸载现象。文中建立的模型可用于复杂土质环境下地铁盾构隧道的安全监测与优化设计。In order to study the longitudinal mechanical behavior of the subway shield tunnel under complex con-ditions,the longitudinal mechanical model of the subway shield tunnel was established based on the two-pa-rameter elastic foundation theory and the state space theory,where the characteristics of internal force and de-formation were analyzed with the shear deformation effect of soil body taken into account,when the subway shield tunnel of longitudinal different stiffness crosses complex geological conditions.The results showed that the cross section of the tunnel in the interface between hard soil layer and the soft soil layer is most prone to damage as a result of reduced mechanics performance arising from the sudden change to the internal force and deformation of the shield tunnel when the subway shield tunnel passes through the hard soil layer and enters the soft soil layer.The large settlement can be offset by increasing the longitudinal stiffness of shield tunnel in the soft soil.The longitudinal internal forces were re-distributed after the shield tunnel was damaged or rein-forced.The greater the local stiffness damage was,the greater the increment of the deflection and the slope of the shield tunnel.At the same time,the internal forces were unloaded in the local stiffness damage sections. The model established in this paper can be used for the safety monitoring and design optimization of the metro shield tunnel under complex soil conditions.

关 键 词：地铁盾构隧道 复杂地质条件 变刚度 双参数弹性地基梁 纵向受力 

分 类 号：TU432[建筑科学—岩土工程]