爆炸荷载作用下饱和半空间中衬砌隧道弹性动力响应IBIEM模拟  

IBIEM Modeling of the Elastic Dynamic Response of a Lined Tunnel under Blast Loading in a Saturated Poroelastic Half-space

作　　者：刘中宪[1] 琚鑫[1,3] 梁建文 Zhongxian Liu;Kin Ju;Jianwen Liang(Tianjin Chengjian University,Key Laboratory of Civil Structure Protection and Reinforcement of Tianjin,Tianjin,300384;Department of Civil Engineering,Tianjin university,Tianjin,300072;Tianjin Institute of Housing Identification and Architectural Design,Tianjin,300318)

机构地区：[1]天津城建大学天津市土木建筑结构防护与加固重点实验室,天津300384 [2]天津大学土木工程系,天津300072 [3]天津市房屋鉴定建筑设计院,天津300318

出　　处：《固体力学学报》2018年第5期492-503,共12页Chinese Journal of Solid Mechanics

基　　金：国家重点基础研究发展计划(2015CB058002);国家自然科学基金项目(51678390)资助

摘　　要：饱和土中爆炸波的传播同单相介质具有显著差别.基于Biot两相介质理论,采用一种高精度间接边界积分方程法（IBIEM）研究了饱和半空间中浅埋衬砌隧道在内部爆炸荷载作用下的瞬态弹性动力反应.通过典型算例,给出了爆炸荷载作用下隧道附近地表位移、衬砌动应力、围岩径向位移和衬砌表面孔隙水压的时程响应,并对比分析了饱和半空间和全空间中隧道动力响应的区别.研究表明：覆土层厚度对浅埋隧道-围岩整体动力响应特征具有明显影响;衬砌表面透水状态对爆炸荷载的时程响应的影响不显著;随半空间饱和介质孔隙率增加,围岩相对刚度下降,进而受隧道内部爆炸影响程度降低,衬砌承担的爆炸作用增大;当和直达波、衬砌内部反射波的峰值叠加作用时,半空间表面反射波对衬砌隧道拱顶附近响应影响显著,使得衬砌动应力幅值、径向位移相比深埋情况大幅度增加.The propagation of blast waves in a saturated poroelastic medium is considerably different from that in a single-phased medium.Based on Biot＇s theory of two-phase medium,a highly-precise indirect boundary integral equation method（IBIEM）is utilized to solve the transient dynamic response of an elastic tunnel embedded in a saturated poroelastic half-space under internal blast loading.The time-history responses of ground displacement,tunnel hoop stress,radial displacement and pore pressure of surrounding rock under blast loading are calculated,and the difference between the time-history responses of the saturated half-space and the entire space is analyzed.The results show that the embedded depth has a significant effect on the dynamic response of shallow-buried-tunnel surrounding rock system;and the boundary drainage condition has little impact on the time-history response under blast loading.With the increase of porosity,the stiffness of saturated rock decreases.Then the influence of blast loading on the surrounding saturated rock reduces,while the blast effects on the tunnel increase.When the direct waves and the reflected waves by the tunnel surfaces are strengthened by the reflected waves from the half-space surface,the tunnel vault is obviously affected by the surface reflection wave,and the amplitude of hoop stress and the radial displacement of surrounding rock are much larger than those of the tunnel in the entire space.

关 键 词：饱和半空间 隧道衬砌 爆炸荷载 间接边界积分方程法(IBIEM) 

分 类 号：U451[建筑科学—桥梁与隧道工程]