复杂应力状态下TBM刀盘裂纹应力强度因子分析  

Analysis of stress intensity factors for a TBM cutter head crack in complex stress states

作　　者：凌静秀[1] 孙伟[2] 杨晓静[1] 练国富[1] 江吉彬[1] 

机构地区：[1]福建工程学院机械与汽车工程学院,福建福州350118 [2]大连理工大学机械工程学院,辽宁大连116024

出　　处：《哈尔滨工程大学学报》2017年第4期633-639,共7页Journal of Harbin Engineering University

基　　金：国家重点研究发展计划(2013CB035402);福建省自然科学基金项目(2015J01181);2014年福建省产业技术联合创新专项资助项目(闽发改高[514]号)

摘　　要：为了预测全断面岩石掘进机(tunnel boring machine,TBM)刀盘的疲劳寿命,本文对其裂纹尖端的应力强度因子进行了研究。以某水利工程的刀盘为研究对象,采用基于子模型技术的有限元法分析复杂应力状态下刀盘裂纹的应力强度因子,并给出了不同裂纹参数对应力强度因子的影响规律,为刀盘裂纹扩展寿命的预测提供输入条件。分析表明,当裂纹位置角为45°或135°时,裂纹尖端的等效应力强度因子最大,对结构损伤最严重;形状比对K_Ⅰ值影响最显著,形状比越大,尖端K_Ⅰ值相差越大,在深度方向的扩展趋势也越强;K_Ⅰ、K_Ⅱ及K_Ⅲ值均随裂纹深度的增加而增大,裂纹尖端最深处以张开型扩展形式为主,而表面点则是3种开裂形式并存。We studied the stress intensity factors of the crack tip of a tunnel boring machine(TBM) cutter head to predict the fatigue life of the TBM.A TBM cutter head in a water tunnel project was studied,and the finite element method based on submodeling technology was used to analyze the stress intensity factors of the cutter head crack under complex stress conditions.The influences of various crack parameters on stress intensity factors were illustrated to provide input conditions for cutter head life prediction.The analysis showed that equivalent stress intensity factors at the crack tip were the largest when the crack position angle was 45° or 135° and it caused the most serious damage to the structure.In addition,the crack shape ratio had the greatest influence on K_Ⅰand a larger shape ratio meant a larger K_Ⅰdifference at the crack tip.This led to an obvious expansion trend in the depth direction.Furthermore,K_Ⅰ,K_Ⅱ,and K_Ⅲ increased with increasing crack depth.The crack tip was dominated by an opening mode crack,whereas the surface points comprised three types of cracks.

关 键 词：TBM刀盘 应力强度因子 裂纹 复杂应力状态 子模型技术 裂纹形状比 疲劳寿命 

分 类 号：TH113.1[机械工程—机械设计及理论]