双裂纹损伤下TBM刀盘结构疲劳寿命分析

Fatigue life analysis of TBM cutter head structure under double crack damage

基于Paris公式建立TBM刀盘的裂纹扩展模型,利用Workbench模拟裂纹的开裂过程,计算出其循环次数与应力强度因子。并改变双裂纹的初始长度、距离、角度,分析多部位损伤时筋板的裂纹扩展寿命。结果表明,裂纹的初始长度越长构件越容易失效,每增加2.5 mm寿命将减少35%,而双裂纹距离对寿命的影响较小,在10%以内。当裂纹方向和受力方向垂直时,构件容易失效,反之则对寿命的影响越小。该研究可为刀盘设计过程中疲劳寿命领域提供参考。

Based on the Paris formula,the crack propagation model of the TBM cutter head was established,and the cracking process of the crack was simulated by Workbench,and the cycle times and stress intensity factor were calculated.The initial length,distance and angle of the double cracks were changed so as to analyze the crack propagation life of the rib when multiple parts are damaged.Results show that the longer the initial length of the crack,the more likely the component will fail,and the life will be reduced by 35%for every 2.5 mm increase,while the double-crack distance has less effect on the life,i.e.,within 10%.When the crack direction is perpendicular to the force direction,the component is prone to failure,and otherwise,the impact on the life is smaller.This research can provide reference for the field of fatigue life in the design of cutter head.