Study On Dynamic Response Of Shield Tunnel Structure And Aviation Oil Pipeline Under Aircraft Dynamic Load

With the acceleration of China’s urbanization process,the urban transportation network is becoming more and more perfect.Therefore,in order to facilitate people’s travel,the urban subway and the airport are connected together,and this connection often leads to undercutting and overlapping.The subway often runs under the airport.On the other hand,the airport aviation oil pipeline is an underground structure of the airport.The aviation oil transported by it is flammable and explosive.Once it is impacted or under great pressure,it will leak,which will cause huge economic losses.Therefore,based on the project of connecting Changsha Maglev East extension line to T3 terminal,this paper uses various research means such as data investigation,numerical simulation and theoretical analysis to analyze the dynamic response of shield tunnel and underground pipeline under aircraft dynamic load.The main research contents and achievements of this paper are as follows:1)The additional stress of different models on the soil layer below the pavement was analyzed by using Boussinesq and layered elastic theory.Taking five typical aircraft types as the research object,the aircraft load was simplified into node load for calculation.Using the elastic layered theory,combined with the overburden thickness of shield tunnel and aviation oil pipeline in practical engineering,the overburden thickness was transformed into the converted overburden thickness.The calculation formula of additional stress under aircraft load was obtained by using the Boussinesq solution,and the magnitude of additional stress was finally obtained.2)By comparing the magnitude of additional stress,a finite element model was selected to carry out numerical simulation,and the influence of aircraft dynamic load on shield tunnel was studied.The finite element model of shield tunneling in Changsha Huanghua International Airport was constructed to simulate the excavation and penetration conditions.The numerical simulation shows that the position of aircraft load was the main factor affecting the deformation of shield tunnel.When the aircraft load was directly above the shield,the deformation of shield tunnel was the largest.3)The finite element model was established to analyze the influence of aircraft dynamic load on fuel pipeline,and the minimum allowable buried depth of pipeline was calculated.By fitting the vertical displacement and deformation curves of fuel pipeline under different buried depths,it was obtained that the buried depth of fuel pipeline needs to be greater than 2.47m.