摘要
结合实例介绍了FLAC 3D软件在地铁隧道地震动力响应方面的应用。利用FLAC 3D软件建立了二维地铁隧道有限元模型,并对地铁隧道进行初始应力场、开挖和简单支护、地震波作用模拟,得到不同埋深情况下双线隧道的单元应力云图、考察点位移值、变形网格云图等。分析得到以下结论:软弱岩层隧道变形严重,弹性模量、摩擦角和内聚力影响较大;随埋深增加,隧道顶部在竖直方向拉应力增长,隧道衬砌位移及内力响应加剧,隧道衬砌顶、肩、两侧等各点位移响应逐渐趋于一致;埋深的增长,使岩体对隧道衬砌的约束增加,地震动力引起的位移和内力响应减弱。
The application of FLAC 3D software in earthquake dynamic response inside subway tunnel is briefly introduced with practical cases,with its help a 2D finite element model is established to simulate the earthquake in tunnels.By this way,the unit stress nephogram at different depthes,the point value of displacement,and the displacement vector model results of the double-track tunnel are obtained.Through analysis,comes the following conclusion：tunnel in soft rock layer has more deformation,the influence of elastic modulus,friction angle and cohesion is greater; with the increase of buried depth,the tensile stress in vertical direction of tunnel top grows,and the compressive stress area spreads to the two shoulders of the tunnel,the numerical value gradually increases; with the increase of buried depth,the response of tunnel lining displacement and internal force increase,but the growth rate decreases;displacements of tunnel lining top,shoulder,and other points on both sides of the tunnel lining will gradually tend to be consistent;the rock layer constraints on tunnel lining increase with the growth of depth,so the response of displacement and internal force induced by earthquake decreases.
出处
《城市轨道交通研究》
北大核心
2014年第4期47-53,共7页
Urban Mass Transit
