Energy Absorption And Crashworthiness Studies On Open Section Thin-Walled Structures

Thin-Walled structures have been widely used in automobiles, ships, trains and collision safety protection facilities as good structure quality efficiency and high energy absorption capacity. Therefore, extensive attentions have been drawn on energy absorption and crashworthiness studies of various forms of Thin-Walled structures. Compared to closed section Thin-Walled, open section Thin-Walled is gradually widely research owing to easy to check the corrosion problem. The deformation modes under impact load and energy absorption of typical Thin-Walled structures are carried out in present work, which put corrugated web beam and bumper as the research object. The detailed research contents are as follows:(1) Based on one dimensional compressive bar structure elastic-plastic buckling study, one dimensional instability of submissiveness principle is extended to two-dimensional thin-walled structure. Combined with the good mechanics performance of corrugated web beam, this thesis systematically introduces instability compliance principles of two-dimensional sine corrugated web beam(2) For sine corrugated web beam structure, the buckling mode of different sine wave orders can be controlled by design of the initial amplitude imperfection of the sine wave webs, and then lead the upper and lower plates in accordance with the predicted progressive, stable and repeatable crush deformation. The relationships of specific energy absorption (SEA) and initial amplitude imperfection could be researched by numerical simulation using Abaqus/ Explicit dynamic analysis and illustrate the influence of energy absorption characteristics and buckling control in different orders of the sine wave beam by comparing the load displacement curve of low-order, mid-order and high-order.(3) This thesis simulate machining process of polypropylene (PP) and long glass fiber reinforced polypropylene (LGFPP) bumper beam using Moldflow. The composite material properties and the residual stress results import Abaqus standard material through the development of Abaqus - Moldflow interface program, using Abaqus/Implict dynamic method of static and dynamic analysis. Compared with metal bumper, for the influence of different materials, impact velocity and residual stresses on the bumper collision resistance were analyzed.