贯穿裂纹管局部柔度系数的理论与试验研究

根据线性断裂力学理论和应变能释放原理,推导了考虑裂纹张开状态的圆周贯穿裂纹管的附加局部柔度方程,利用自适应的Simpson数值积分方法计算裂纹引起的局部柔度系数,并根据得到的局部柔度系数,建立了以扭转弹簧模拟裂纹行为的裂纹管模型。进行了裂纹管的动力模型试验,通过裂纹管模型固有频率的试验值与理论值对比分析验证局部柔度系数的正确性。研究结果表明:裂纹管固有频率的试验值与使用"弹簧铰"裂纹管模型求得的理论值基本吻合,验证了贯穿裂纹管局部柔度系数的合理性。

Local flexibility of a pipe with a through circumferential crack

Abstract: The local flexibility equations of pipe with a through circumferential crack were derived from linear fracture mechanics，combined with strain energy release rate. An adaptive Simpson quadrature-revisted was used to perform the numerical integration to obtain the local flexibility coefficients. And then, the crack model of pipe simulated by torsional spring was established based on proposed local flexibility. Moreover, the dynamic test of the through circumferential cracked pipe was used to validate the proposed resolution for local flexibility by comparing the theoretical results to experimental results. The research results demonstrate the natural frequencies of cracked pipe obtained by means of proposed local flexibility and the dynamic test show good agreement, which indicates that the presented resolution for calculating local flexibility is reasonable.