砂浆断裂过程区的研究  

Fracture process zone of mortar

作　　者：马錩臣[1] 冯乃谦[2] 

机构地区：[1]东北农业大学水利与建筑学院,黑龙江哈尔滨150030 [2]清华大学土木与水利学院,北京100084

出　　处：《混凝土》2008年第10期95-99,共5页Concrete

摘　　要：对砂浆三点弯曲加载梁试件载荷—裂纹口张开位移—初始裂纹尖端张开位移—沿初始裂纹及韧带直线方向若干点张开位移全曲线进行了研究。结果表明,在该全曲线下降段沿初始裂纹及韧带直线方向张开位移近呈线性分布;裂纹口张开位移与平均裂纹张开角呈线性关系,该关系不决定于初始裂纹相对长度,但决定于试件高度。提出断裂过程区长度估计值公式,证实了临界应力强度因子的初始裂纹长度和试件高度尺寸效应来源于试件在最大荷载及加载过程中断裂过程区长度的产生和变化。The complete curves of load-crack mouth opening displacement-initial crack tip opening displacement-the opening displacements at several points along initial crack and its ligament were determined by using three point bend beams Of mortar.The results show that there exists a linear distribution of opening displacement along initial crack and its ligament under the descending part of above-mentioned complete curves, and there is a linear relation between average crack angle and crack mouth opening displacement and the relation is independent of initial relative crack length but depends on beam height.In addition, an estimate formula of fracture process zone length is put forward, and it is ascertained that the source of size effect of critical stress concentration factor is the change of fracture process zone length at the maximum load and under the descending part of load-rack mouth opening displacement complete curves.

关 键 词：砂浆 断裂过程区 裂纹张开位移 尺寸效应 临界应力强度因子 断裂能 

分 类 号：TU528.01[建筑科学—建筑技术科学]