工程车辆FOPS冲击试验中落锤塑性变形研究

为了对工程车辆的落物保护装置(FOPS)进行可靠性试验提供理论依据,采用冲击动力学的塑性波两侧的动量平衡理论对工程车辆FOPS受冲击时落锤的动态响应进行了研究,建立了锤头变形的基本方程,绘制了方程相应曲线;建立了锤头在冲击过程中任一瞬时变形长度和非变形长度的数学模型,找到了工程应变和冲击速度之间的曲线对于塑性大变形的突变点及影响落锤变形的各个因素和控制变形的依据。为减小落锤的蘑菇形尺寸,降低锤头的材料成本,多次重复使用落锤,进行合理的落锤结构设计指明了方向。

Study of drop hammer plastic deformation at engineering vehicle FOPS impact test

It is necessity to take an impact test for FOPS in laboratory in order to install falling object protective structures at engineering vehicle and check its dependability. It is important to rational design the drop hammer. Authors study the dynamic response of dropping hammer during the FOPS of engineering vehicle being impacted with the momentum balance theory,establish the mathematical model of plastic deformation for dropping hammer at the end of impact and draw the curve of the formula. The factors influencing the deformation of hammer have been found out and the strategies for the control of the deformation are discussed. The plastic big deformation mutation point of curve have been found out between engineering strain and impact speed. The mathematical model for the relations between the hammer length after deformation and that before deformation at arbitrary time provides the theoretical foundation for the study of the plastic deformation of the dropping hammer.