作　　者： ; ; ;

机构地区： 华南理工大学土木与交通学院

出　　处： 《工程力学》 2010年第6期127-132,共6页

摘　　要： 分别应用裂缝尖端应力场Westergaader解和Muskhelishvil解,推导了裂缝尖端微裂区轮廓线及特征尺寸的表达式;并根据幂指数描述的应变软化模型,给出了考虑应力松弛影响的断裂过程区(FPZ)总长及等效FPZ长度的解析表达式,探讨了三种脆性破坏强度准则及材料参数对FPZ尺寸的影响。分析结果表明:由莫尔强度准则及最大拉应变准则确定的FPZ轮廓均随拉压强度比和泊松比的减小而逐渐增大,并趋近于由最大拉应力准则确定的FPZ边界;由局部解得到的FPZ尺寸均比全场解小,且仅在应力水平较小、试件很大时适用。 The contour and characteristic sizes of a micro-crack zone ahead of a Fracture Process Zone（FPZ） were derived by the local solution based on the stress functions of Westergaader and the whole solution of the crack tip stress field based on Muskhelishvil results,respectively.Furthermore,the size and effective size of FPZ are solved by the use of a power exponent model considering the effect of strain softening.Meanwhile,the influences of three strength criterions of brittle failure on FPZ sizes are also studied.The discussion show that FPZ contour sizes determined by Moiré criterion and maximum strain criterion increase with the decreasing tensile-compressive strength ratio and Poisson ratio,and approach that of the maximum stress criterion.The size of FPZ deduced by local solution is only suitable for a larger specimen under a lower stress level.

关 键 词： 断裂力学 断裂过程区 应变软化 强度准则 解

领　　域： [建筑科学] [交通运输工程] [理学] [理学]