含裂纹的梭形薄壁圆柱壳结构应力强度因子分析研究

Study on stress intensity factors of thin-walled shuttle cylinder structure with cracks

应力强度因子是表征裂纹尖端应力场奇异强弱的物理量,对裂纹的扩展和构件失效具有一定的意义,针对梭形薄壁圆柱壳结构断裂问题,基于J积分理论,采用有限元方法研究了含有环向裂纹的梭形薄壁圆柱壳结构在偏心受压下的断裂力学响应,分析了荷载的大小、偏心度、裂纹长度、梭形结构的楔率对裂纹应力强度因子的影响,计算结果表明:裂纹长度、荷载以及楔率对应力强度因子影响很大,而且这些参数是相互影响的.最后根据计算数据拟合出偏心受压梭形圆截面的应力强度因子的计算公式,并和相关的计算结果进行了比较,证明了该公式的可行性.

The stress intensity factor（SIF） is an important parameter which reflect the stress intensity at the tip of cracks. The study of SIF has a certain significance for crack extension and failure of structure. Based on d integration theory, fracture mechanical be- havior of eccentric compression thin-walled shuttle cylinder structure with cracks was studied using the finite element method. The influence of load, crack lengths, eccentricity and tapering ratio on the stress intensity factor was analyzed numerically. The numerical results show that the crack lengths, load and tapering ratio have significant effects on the stress intensity factors. Moreover, there are three factors, i.e. crack lengths, load and tapering ratio, which influence each other. The calculation formula of stress intensity factor of eccentrical compression thin-walled shuttle cylinder structure with cracks was proposed based on the numerical results. The results were compared with the relevant stress intensity factors calculated by others and the comparisons show the feasibility of the calcula- tion formula of stress intensity factor.