车身结构应力的免卸载测量法  

A Stress Measurement Method for Vehicle Body Structure Without Unloading

作　　者：那景新[1] 刘浩垒 王文辉[1] 秦国锋[1] 慕文龙 冯原[1] 

机构地区：[1]吉林大学,汽车仿真与控制国家重点实验室,长春130022

出　　处：《汽车工程》2017年第11期1294-1297,1324,共5页Automotive Engineering

基　　金：国家自然科学基金(51375203)资助

摘　　要：为简化车身结构应力的测量过程,并能测得车辆自重导致的应力,基于线性系统和小变形假定,提出了一种结构应力的免卸载测量方法。该方法在无需卸去被测车辆自身零部件和其他负载的情况下,让被测车辆分别向左、右倾斜相同的角度,利用车辆倾斜引起结构应变的改变,间接地计算出测点应力。基于该方法,进行了一钢架结构试验,对比了免卸载测量法与传统卸载再加载的方法所测得结构应变值,平均误差为3.46%;又进一步进行了实车试验,对比了实车试验的应力值与有限元分析所得应力值,平均误差为6.78%。两个试验结果都证明了该方法的准确性和可行性。To simplify the stress measurement process of vehicle body structure,and enable the measurement of stress caused by the dead weight of vehicle,a structure stress measurement method without dismantling and unloading is proposed based on the assumption of linear system and small deformation.With the method,under the conditions of without dismantling the components of vehicle and removing other loads,the vehicle to be measured is tilted to the left and right successively by the same angle,leading to the change of structure strain,by which the stress at measured point is indirectly calculated.Based on the method a test on a steel-frame structure is conducted to compare the structure strain obtained by the methods of with and without dismantling and unloading,resulting in an average error of 3.46%.Then a real vehicle test is further performed to compare the stress obtained by test and finite element analysis,getting a result with an average error of 6.78%.The results of two tests all verify the correctness and feasibility of the method proposed.

关 键 词：车身 自重载荷 免卸载测量 应变 应力 倾角 

分 类 号：U463.82[机械工程—车辆工程]