Investigation Of Dynamic Response Mechanism Of High-speed Railway Tunnel With Lining Cavity

For the current long-term travel is often used in high-speed rail,the tunnel is an indispensable part.With the surge in tunnel engineering,the series of safety problems can not be ignored,the emergence of various diseases threaten the safety of traffic,so the study of the disease is particularly necessary tunnel.This paper relies on the National Natural Science Foundation of China(U1434211),and selects the hollow defects behind the lining of the high-speed railway tunnel as the research object,and studies the dynamic response law under the vibration load of the train.At the beginning of the design,the lining and the surrounding rock are closely integrated with each other,but due to the latter part of the environment,construction,operation and a series of factors,resulting in different levels of lining behind the cavity,and defective high-speed rail tunnel under the action of vibration The impact of the hollow has a hidden,empty repair is difficult,so the study of its impact under the vibration load is particularly urgent.The main contents and conclusions of this paper are as follows:(1)Based on the data of existing tunnels and train operations monitoring,combined with some field observations,summarize the shape and size characteristics of the voids in the lining,determine the grading criteria and select the geometric dimensions of the typical research objects;(2)Based on the theoretical study of the initial microdeformation,the elastic-plastic damage model of the tunnel lining structure is deduced.On the basis of this,the elastic-plastic damage release rate and the damage surface are introduced,The damage evolution function of the structure and the corresponding constitutive relation;(3)Based on ABAQUS software,the finite element model is established to analyze the dynamic response of dynamic vibration under the action of train under different working conditions;(4)Summarize the stress and deformation behavior of the tunnel structure and its influence on the defective part of the tunnel structure and the safe operation of the tunnel under the repeated dynamic load.