带单侧裂纹楔梁动力特性研究

DYNAMIC BEHAVIOUR INVESTIGATION OF TAPER BEAM WITH SIDEWISE CRACK

由于裂纹存在引起构件局部柔度的变化，本文用线弹性断裂力学理论导出裂纹所释放的应变能，由Ｃａｓｔｉｇｌｉａｎｏ 定理得出局部柔度矩阵诸元素，据此来修正楔形梁的刚度矩阵，借助梁有限单元法，求解带裂纹楔形梁的动力特性，并对裂纹相对深度、裂纹位置、梁的长宽比、宽厚比。

Emergence of crack causes local flexibility variation of the component.A linear elasticity theory of fracture mechanics is applied to deriving the strain energy released by the crack.According to Castigliano theorem,elements of local flexibility matrix are obtained,which can correct the stiffness matrix of the taper beam.The dynamic behaviour of the taper beam has been found out by means of finite element method.The effects of relative depth of crack,crack location,ratios of length to width and width to taper thickness on natural frequency have been numerically investigated and the relevant experiments have been conducted to testify the calculation results.