Study On Dynamic Response And Failure Mode Of Stiffened Steel Plate Under Impact

The purpose of this study is to investigate the dynamic response and failure mode of stiffened steel plates under different impact loads.Due to its high strength and good performance,steel plate structure has been widely used in industry and various infrastructures.But at the same time,the steel plate structure may be subjected to accidental loads such as impact,explosion,and so on.The steel plate structure is damaged under impact load.Therefore,it is very important to study the dynamic response and damage of steel plates under impact load.Therefore,the finite element analysis software ABAQUS is used to establish the stiffened and un-stiffened steel plate models.The dynamic response and damage of steel plates under impact load are studied.The main contents of the research are as follows:(1)An effective finite element model is established.Considering the different arrangements of stiffeners,four kinds of steel plate models with and without stiffeners are established by ABAQUS.The refined mesh is used,the strain rate effect of steel is considered,and the Johnson-Cook constitutive model is used.By controlling the ratio of artificial pseudo strain energy to total energy and internal energy,the reliability of finite element simulation results is ensured.(2)Dynamic response parameter analysis was carried out.Five parameter combinations that affect the dynamic response of steel plates are selected: impact velocity,impact mass,impact position,stiffener arrangement,and boundary condition.The effects of the parameters combination on the displacement,impact force response,kinetic energy,and internal energy of the steel plate are analyzed.The results show that the impact speed and impact mass are the main factors affecting the dynamic response of steel plates.The maximum displacement increases with the increase of impact velocity and impact mass.At the impact mass of 3tons,the maximum displacement varies with the impact velocity,thus,from 96 mm for 5m/s to 240 mm for 15m/s both for M1,40 mm for 5m/s to 109 mm for 15m/s both for M2,while for M3,the displacement varies from 51 mm for 5m/s to 148 mm for 15m/s,and finally,the displacement varies from 75 mm for 5m/s to 218 mm for 15m/s both for M4.Compared to other plate models,the unstiffened plate deforms rapidly with a maximum deformation of 140 mm for 15m/s.When the impact mass is the same,the deformation of the steel plate increases with the increase of impact velocity.(3)The damage judgment method is studied.The deformation of the steel plate under impact is analyzed.The damage of the steel plate is mainly concentrated in the impact point,mainly the interaction point between the steel plate and the impact block.The damage degree of steel plate under different impact parameter combinations is divided into three impact damage modes.Based on the maximum displacement criterion,the range of the ratio of the center displacement of the steel plate to the calculated span is given as the judgment basis.