Analysis On Dynamic Response Of Cross-river Road Tunnel Under Vehicle Loading

The continuous action of vehicle random dynamic load is one of the possible causes of longitudinal differential settlement of the cross river highway tunnel.Taking the Nanjing Yangtze River Tunnel as an example,the random dynamic load of the vehicle by the simulation calculation is put on the three-dimensional finite element model of the tunnel,to analyze the vibration response of the soil around the tunnel.The main research contents are summarized as follows:1.Under the road roughness excitation,the dynamic analysis model of the random vehicle load is established by using 1/4 vehicle dynamic analysis model.The MATLAB/Simulink program is used to simulate the random dynamic load of the vehicle,then the dynamic load time history curve of the dynamic vehicle model is derived,and the relationship between random vehicle dynamic load and vehicle speed,road grade and vehicle type is discussed.The Parameter sensitivity analysis of the three factors shows that the sensitivity of the three factors affecting the random vehicle load from large to small is:road grade>vehicle type>vehicle speed.2.Chose two typical test sections of the Nanjing Yangtze River Tunnel to establish the three dimensional finite element model of the tunnel in soft soil layer and sand layer by the ANSYS finite element software.Apply the random dynamic load of the vehicle that has been calculated to the three-dimensional finite element model of the tunnel,then the influence of vehicle speed,road class,vehicle position and the number of vehicles on the dynamic response of the soil around the tunnel is simulated and discussed.In addition,under the same dynamic load of the vehicle,the stress responses of the soil of the left tunnel and the right tunnel is different,the result investigates the influence of different soil properties around the tunnel on the dynamic response of the soil.