Study On Mechanism Of Flood Damage To Superstructure Of Slab Bridge

As a common section form of superstructure of medium and small span bridges,plate girder is widely used in river crossing and coastal bridges due to its simple structure,easy installation and low cost.When natural disasters such as flood,storm surge and tsunami occur,many superstructures of bridges will shift and slide under their action.There is no systematic research on the mechanism of plate girder water damage in the existing literature,so it is necessary to carry out the research on the mechanism of plate girder water damage.In this paper,through the experimental study in the wave-current tank and the numerical calculation based on ANSYS fluent,the characteristics and generation mechanism of the force of flood,solitary wave and solitary wave breaking surge on the plate girder are analyzed,and the influencing factors of the force and the possible failure forms of the plate girder are analyzed:1.In order to solve the problem of how the water acts on the plate girder and causes the damage of the plate girder,this paper makes an experimental study on the flood effect of the plate girder,and establishes a numerical calculation method for calculating the flood force of the plate girder based on the experimental results,and obtains the characteristics,generation mechanism and influencing factors of the force of the plate girder under the action of the flood,as well as the possible damage forms of the plate girder under the action of the flood.2.In order to solve the problem of how the solitary wave acts on the plate girder and leads to the failure of the plate girder,an experimental study on the solitary wave action of the plate girder is carried out in this paper.Based on the experimental results,a numerical calculation method for calculating the solitary wave force of the plate girder is established,and the characteristics of the force of the plate girder under the solitary wave action are obtained The mechanism and influencing factors,and the possible damage forms of the plate girder under the action of solitary wave are analyzed.3.In order to solve the problem of how the solitary wave breaking bore acts on the plate girder and leads to the failure of the plate girder,an experimental study on the solitary wave breaking bore of the plate girder is carried out in this paper.Based on the experimental results,a preliminary numerical calculation method for calculating the breaking bore force of the plate girder is established The mechanism and influencing factors,as well as the possible damage forms of the plate girder under the action of solitary wave breaking bore.