浅埋偏压小净距隧道大型振动台实验研究  

Large-scale shaking table model test study of unsymmetrical loading neighborhood tunnel with shallow depth

作　　者：江学良[1,2] 连鹏远 杨慧[1,2] 王飞飞[1,2] 牛家永 

机构地区：[1]中南林业科技大学土木工程与力学学院,长沙410000 [2]中南林业科技大学岩土工程研究所,长沙410000

出　　处：《应用力学学报》2017年第3期456-463,共8页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(51204125;51404309)

摘　　要：浅埋偏压小净距隧道具有与其它形式隧道不同的受力特点,其地震响应特性也必然不同于其它隧道。基于相似理论设计并完成了浅埋偏压小净距隧道大型振动台模型实验,研究了小净距隧道分别在X(水平)向、Z(竖直)向、XZ双向(水平竖直同时输入)多种工况汶川地震波作用下隧道衬砌加速度和动应变响应规律。实验结果表明:(1)衬砌加速度受地震波的入射方向影响较大,且Z向的影响大于X向,XZ双向的影响大于单向,左洞隧道的加速度响应大于右洞隧道;(2)衬砌应变受地震烈度的影响较大,隧道衬砌在地震作用下承受拉压循环荷载,以受拉为主,右洞隧道衬砌的动应变响应大于左洞隧道;(3)综合衬砌加速度与动应变的响应分析,左洞隧道的左半部分和右洞隧道的拱脚是隧道衬砌在地震作用下容易发生损坏的部位,在进行设计配筋时应特别注意。对于浅埋偏压小净距隧道衬砌进行抗震设计计算时,应考虑Z向地震的影响。研究成果可为浅埋偏压小净距隧道工程的抗震设计提供参考。Unsymmetrical loading neighborhood tunnel with shallow depth is compared with tunnels of other forms;their stress characteristics and response under seismic action are quite different.Based on similar theory,a large-scale shaking table model test of unsymmetrical loading neighborhood tunnel with shallow depth is completed.Neighborhood tunnel’s seismic response characteristics of acceleration and dynamic strain in Wenchuan wave with X(horizontal),Z(vertical)and XZ(horizontal and vertical)excitation direction are studied in the test of multiple conditions.The results show that:(1)The incident direction of seismic wave has great influence on the acceleration of tunnel lining,and the influence of Z direction seismic wave is greater than X direction,and the influence of XZ bidirectional seismic wave is greater than one way.The acceleration response of the left tunnel is larger than right tunnel.(2)The strain of lining is greatly influenced by seismic intensity.Under the action of earthquake,the tunnel lining is subjected to tensional and compressive cyclic loading,mainly in tension.The dynamic strain of the right tunnel is larger than left tunnel.(3)Through comprehensive analysis of acceleration and dynamic strain response,the left part of the left tunnel and the right tunnel’s arch foot are areas prone to damage in earthquake,so special attention should be paid during the design of reinforcement.For the seismic design and calculation of the unsymmetrical loading neighborhood tunnel with shallow depth lining,the influence of Z direction seismic wave should be considered.The conclusions provide useful guidance to the seismic design of the unsymmetrical loading neighborhood tunnel with shallow depth.

关 键 词：浅埋偏压小净距隧道 振动台模型实验 加速度响应 动应变响应 

分 类 号：U45[建筑科学—桥梁与隧道工程]