全断面隧道掘进机刀盘裂纹尖端应力强度因子收敛性分析

Convergence Analysis of Stress Intensity Factor at Crack Tips for TBM Cutterheads

针对全断面隧道掘进机刀盘裂纹损伤及寿命预测等工程问题,提出了基于子模型技术的应力强度因子求解方法,并用含裂纹的矩形钢板对该方法进行了验证,分析了裂纹网格参数对刀盘裂纹尖端应力强度因子的收敛性影响。结果表明,钢板的应力强度因子数值和理论计算结果最大相对误差为3.6%。同时得到了保证刀盘应力强度因子求解精度和效率的裂纹单元网格参数,为结构的裂纹扩展寿命预测提供了参考。

Aiming at the engineering problems such as crack damage and life prediction of TBM cutterheads, a solution method of stress intensity factors was proposed based on the sub-model tech-nique and it was validated by a rectangular steel plate with a crack. Then the convergence effects of crack mesh parameters on stress intensity factors at the crack tips of cutterheads were analyzed. The analysis results show that the maximum relative errors of numerical and theoretical results are as 3.6%. Besides,the crack element mesh parameters were obtained that ensured both of the accuracy and efficiency for cutterhead stress intensity factors solutions？ which may provide a reference for the crack growth life prediction of structures.