Investigations On The Crashworthiness Of Vehicle Crash Box With Continuous Corrugated Structure

As the number of automobiles increases,road traffic becomes increasingly complex,resulting in frequent traffic accidents and causing significant human and economic losses.To reduce casualties and property damage in traffic accidents,improving the passive safety performance of automobiles is particularly important.Corrugated thin-wall structures,as a regular and efficient energy absorption device,have gradually attracted the attention of researchers.However,traditional corrugated thin-wall structures suffer from low energy absorption,unstable crushing process,and difficulty in determining the crushing starting point.In this study,a new type of corrugated structure,called equidistant continuous corrugated structure,was designed based on the traditional equidistant discrete corrugated structure.The use of continuous corrugations in the design made the crushing process more orderly,with a natural transition from one corrugation to the next,reducing the peak load during the crushing process and smoothing the entire crushing process.Furthermore,in order to further improve its crashworthinesss and enhance the passive safety performance of automobiles,in-depth research was conducted on the continuous corrugated structure.The main research contents of this paper are as follows.(1)Uniaxial compression tests of the continuous corrugated structure were carried out for vehicle crash boxes.3D printing technology was used to prepare continuous corrugated structure specimens,and quasi-static axial compression tests were conducted based on a universal testing machine.The experimental results show that with the increase of the number of corrugations and the amplitude of corrugations,the crashworthiness of the continuous corrugated structure also improves,which preliminarily reveals the influence of corrugation design parameters on the crashworthiness of equispaced continuous corrugated tubes.(2)Finite element simulations of the continuous corrugated structure for automobile crash boxes were conducted.Accurate material models were established based on tensile tests,and finite element models of continuous corrugated structures were established.The accuracy of the finite element model was verified by comparing it with the experimental results.Finally,Law of conservation of energy and plastic hinge theory were used to construct a theoretical model of the energy absorption characteristics of the continuous corrugated structure vehicle crash box.The results showed that the crashworthiness of equidistant continuous corrugated tubes was better than that of equidistant discrete corrugated tubes.The experimental study preliminarily found that the crashworthiness of the continuous corrugated structure gradually improved with the increase of the number and amplitude of corrugations.(3)Crashworthiness studies were conducted on rib-filled and gradient crash boxes,and the crashworthiness of vehicle crash boxes was comprehensively evaluated.Finite element models of X-shaped and Y-shaped rib-filled continuous corrugated crash boxes and gradient corrugated energy absorption boxes were constructed,and crashworthiness simulations were carried out.The study found that the total energy absorption of equidistant continuous corrugated tubes filled with X-shaped ribs was greater than that of Y-shaped ribs,and the peak load of the former was greater than that of the latter.The crashworthiness of the two types of gradient continuous corrugated structures was similar,but the deformation pattern of odd-amplitude variable-period gradient continuous corrugated tubes was irregular,making the variable-amplitude gradient continuous corrugated tubes more universal.Finally,multiple indicators were comprehensively evaluated for a total of 96 continuous corrugated tubes,and the crashworthiness scores of all the continuous corrugated tubes were calculated.The continuous corrugated structure vehicle crash box designed in this paper is a potential efficient energy absorption structure,which can significantly reduce peak loads,smooth the crushing process,and improve the passive safety of vehicles.It can provide reference for related research and design.