Dynamic Plastic Response Of Stiffened Plates Subjected To Explosive Impact Loading

The problem of stiffened plate has always been concerned, for strength design, it isimportant to study on how the stiffened plate resists the impact load. The paper combinestheoretical deduction with finite-element analysis, systematically analyzes plasticdeformation of stiffened plate suffered by blast impact loading.By consulting relevant literature and data, the thesis summarizes the plastic dynamicresponse problem of stiffened plate, describes the failure modes of stiffened plate,including plastic deformation, tensile failure and shear failure. Based on the rigidity ofstiffener, plastic deformation is divided into: integral deformation mode, local deformationmode and mixed deformation mode.The paper analyzes the plastic deformation of flat plate and single stiffener plateunder blast loading, by using torque balance theory, gives the formula for computing finalmidpoint deflection of flat plate and single stiffener plate, selects examples for theoreticalsolving, and uses nonlinear dynamic software ABAQUS to simulate the examples,compares the two results. The results show that the theoretical solution is in goodagreement with the finite element solution, prove the feasibility of theoretical method.The paper discuss the factors in the plastic deformation of stiffened plate from blastload by using ABAQUS, including geometry structure form of stiffened plate, height andwidth of the stiffener, wave mode of blast load, parameter of strain rate effect etc. Bychanging the factors，observe the midpoint deflection of stiffened plate from finite elementsimulation, draw out corresponding time-deflection curve of the midpoint. The simulateresults show that geometry structure form of stiffened plate has more obvious influence onresistance of stiffened plate under blast loading; in the stiffened plate, compared with thewidth of the stiffener, the height of the stiffener has more obvious effect on the resistanceof the plate; peak value and its presentation time of the blast loading influences the size ofthe final plastic deformation of stiffened plate; strain rate effect has greater influence onthe final plastic deformation of stiffened plate.