| With the continuous improvement of our national transportation network,more and more transportation routes intersect and overlap each other.Airplanes and subways are the representatives of urban transportation modes,and there are also projects of multi-line overlapping shield tunnels crossing the airport runway.Due to the impact of tunnel construction on the airport runway and existing tunnels,how to ensure the normal operation of the airport and effectively control the deformation of the existing tunnels has become a problem that needs to be solved in the shield tunnel crossing project.Based on the new tunnel crossing the airport flight area in the reconstruction and expansion project of Kunming Changshui International Airport,this paper adopts the method of combining numerical simulation and model test to study the deformation of the airport runway and the existing tunnel during the construction process,and analyzes different crossing conditions.Deformation law of the airport runway and existing tunnel,and the effect of aircraft loads on airport runways and tunnels.The following is the content of the research paper:(1)Analyze the minimum buried depth of shield tunnels under non-stop conditions.Combined with the previous shield tunnel burial depths in Kunming,a numerical simulation model of shield tunnels with different burial depths was established,and the minimum burial depth at which the shield tunnel construction would not affect the upper airport runway under static force was analyzed.(2)Analyze the dynamic responses of airport runways and existing tunnels under various crossing schemes.Under the obtained minimum burial depth,the influence of shield tunnel construction on the airport runway and existing tunnels was analyzed,and the deformation law of the airport runway and existing tunnels was found by considering different crossing methods,crossing angles,and interlayer soil thickness.get the best traversal plan(3)Analyze the dynamic effects of aircraft moving loads on the tunnel stability.Through the collection of data,the relevant parameters of the largest civil aviation aircraft in the world are obtained,and the aircraft load is simplified.The aircraft load is applied to the crossing scheme,and the dynamic response of the airport runway and the existing tunnel under the action of the aircraft load is studied.(4)Carry out model tests under the action of conventional gravity.Under the guidance of similar theory,the drainage method was used to simulate the excavation unloading,formation loss and simultaneous grouting process during shield tunnel excavation.The model test results were compared with the finite element simulation results. |
