摘要
为了考察人工预制裂缝宽度对确定岩石断裂韧度的影响,采用大理岩制作了含有不同预制裂缝宽度的中心圆孔裂缝平台巴西圆盘试件(hole-cracked flattened Brazilian disc,HCF-BD),在RMT150B试验机上进行试验,对不同预制裂缝宽度圆盘的应力强度因子进行有限元计算,并对测试方法进行了研究。结果表明,采用将预制裂缝宽度视作零宽度裂缝方法确定的断裂韧度值偏低,给出了一种采用最小载荷和最大无量纲应力强度因子确定岩石断裂韧度的新方法,该方法能够消除预制裂缝宽度对圆盘试件测定岩石断裂韧度的影响。
In order to investigate the influence of prefabricated crack width on determining rock fracture toughness accurately, some marble specimen of hole-cracked flattened Brazilian disc （HCFBD） with different prefabricated crack widths were prepared. Loading experiments were accomplished on test machine RMT150B. Stress intensity factor of disc specimens with different prefabricated crack widths was calibrated by finite element method, and the test methods were also studied. Results show that the tested fracture toughness values were tow, when regarding the prefabricated crack width as zero-width crack. A new method to determine rock fracture toughness is presented in this paper, which adopts the minimum load and the maximum dimensionless stress intensity factor. This method can eliminate the influence of prefabricated crack width on the determining rock fracture toughness of disc specimen.
出处
《实验力学》
CSCD
北大核心
2013年第4期517-523,共7页
Journal of Experimental Mechanics
基金
国家自然青年基金(51004043)
河南理工大学博士基金(B2008-66648270)资助
关键词
预制裂缝宽度
岩石断裂韧度
中心圆孔裂缝平台巴西圆盘
最大无量纲应力强度因子
prefabricated crack width
rock fracture toughness
hole-cracked flattened brazilian disc （HCFBD）
maximum dimensionless stress intensity factor
