Dynamic Response Characteristic Analysis On Complex Lining Of Tunnel Under Earthquake

Currently the city's main road tunnel usually construct single hole three lanes,four lanes and other large section tunnel,and more and more,While the seismic research of domestic large section tunnels is less,in this paper research dynamic response of the complex lining on the background of Chongqing Shuangbei tunnel.The main work as follows:1.Summarizing tunnel damage data that has occurred.Investigate the destruction form,mechanism and its influencing factors of the tunnel under earthquake.Reseaching Viscoelastic artificial boundary condition,the importing time of the seismic waves,baseline drift correction and filtering on seismic wave and so on several important issues that have a major impact on the tunnel seismic dynamic simulation results.And find an inputting method of initial stress field in the dynamic calculation with ANSYS software.2.Building three-dimensional numerical model of large section tunnel hole body complex lining to carry on seismic response calculation and analysis under earthquake,change one parameter,keeping the other parameters constant.Studying displacement,acceleration,velocity,stress time data at key parts of complex lining in different depth,different support strength,different levels of surrounding rock,different seismic intensity.And accordingly analyze dynamic response discipline of lining structure under earthquake.3.Based on strength verification method when reinforced concrete eccentric compressed destroyed.Calculated safety factor variation discipline at key parts of complex lining in different depth,different support strength,different levels of surrounding rock,and contrast analysis.The study found the deeper tunnel depth,the smaller the seismic response,the depth of 8D is the dividing line of deep shallow depth of seismic response.the greater lining support strength,the higher safety factor,but its force greater.The better the surrounding rock,lining horizontal shear dislocation less obvious,the stress mutation in the surrounding rock transition zone is easy to damage the lining.The greater seismic intensity,the greater response to the lining,the displacement in the direction of the seismic wave excitation is much larger than the other direction of displacement.In the complex lining structure the safety factor in the sidewall is the lowest,is the weakest link under earthquake.4.Based on the study in this paper got the safety factor variation discipline in the large section complex lining tunnel,proposed appropriate damping measures recommendations in the large section tunnel to provide a reference in design and construction of the large section tunnels anti-damping.