Dynamic Response Analysis Of Continuous Rigid Frame Bridge Under Impact Load Of Debris Flow

Debris flow is a common natural disaster in mountainous areas,especially in the southwestern region of China.Debris flow with the sudden burst,strong,destructive,wide range of characteristics led to debris flow disaster in the event of serious consequences.With the development of mountain economy and the intensification of environmental pollution,the probability of debris flow disaster in engineering facilities such as bridges and bridges in roads and railways has also increased.Due to the characteristics of mountainous terrain,geology,hydrology and environment,the selection of continuous rigid frame bridge type is also increasing.Especially,deep foundation pit,high pier and long-span bridge are one of the best schemes.Therefore,the dynamic response of continuous rigid frame bridge with debris flow is studied in this paper.In this thesis,the basic characteristics of debris flow are briefly introduced,and the important parameters affecting the impact of debris flow are studied.The debris flow control equation,rheological model and numerical analysis method are analyzed in detail.The rheological model and numerical analysis method of this simulation are determined.The CFX module used to calculate the hydrodynamics in the software "Ansys Workbench" simulates the impact of the debris flow on the three different types of piers of the continuous rigid frame bridge.The volume distribution of the debris flow can be obtained,the velocity streamline and the pier Pressure diagram.This design has a theoretical and engineering reference value for the protection of pier and pier under the impact of debris flow.By simulation of the two-way fluid-solid coupling of debris flow on a real Mojiazhai dual-line railway bridge,structural deformation and stress are obtained.And the pressure obtained by the impact of the debris flow on the pier is introduced as the boundary condition of the structure,and the simulation is carried out again.The results of two-way fluid-solid coupling and unidirectional fluid-solid coupling are compared and analyzed.