残余应力对构件固有频率影响的讨论

INFLUENCE ON THE NATURAL FREQUENCY OF COMPONENT WITH RESIDUAL STRESS

以轴焊缝存在残余应力的矩形板为例 ,建立其残余应力的数学模型。推出存在残余应力时四边简支矩形薄板的固有频率计算公式。从理论和实验的讨论中得出 ,残余应力越大 ,固有频率变化越大 ;频率阶数越高 。

According to the distribution feature of welding residual stress on plate with welding seam along axes, a mathematical model of the welding residual stress is suggested. A formula of natural frequency of simple supported quadrate thin plate with welding residual stress is presented. Using the formula, influenle on the natural frequenly of component with residual stressis analysed. Some conclusions of experiment are obtained from the experiment ofmodal analysis.The calculation results are compared with experiment results, and some conclusions have been obtained. They are: if other factors are not changed, (1)the larger the residual stress is, the langer the chang of natural frequency is. (2)the higher the rank number are, the larger the influence of residual stress on frequenly is, (3)the influence of residual stress on frequenly of large density component is smaller than that of the small density ones,(4)the influenle of residual stress on frequenly of component with large measure a?b is smaller than that with small measure a?b .