Theoretical Analysis and Experimental Verification of Crack Initiation Characteristics of Compression-Shear Plane Crack with Hydraulic Pressure

• 作者: Bangxiang Li Song Yu Weishen Zhu Yajuan Xie Ziyao Xu
• 来源期刊: 力学国际期刊(英文)
• 学科: 医学
• 关键词: Compression-Shear PLANE CRACK Stress Intensity Factor Experimental Verification CRACK INITIATION CHARACTERISTICS
• 年，卷（期）: lxgjqkyw_2018,（9）
• 页码范围: 378-386
• 页数: 9页
• 分类号: R73

摘要

In this paper, the crack initiation characteristics of compression-shear plane crack with hydraulic pressure were studied by using theoretical analysis and experimental verification methods. The formula derivation process of stress intensity factor of crack tip and open-type crack initiation angle and initiation strength was expounded in detail. Cement mortar specimens prefabricated with open-type crack were made for biaxial compression test. The results show that the mode I stress intensity factor is inversely proportional to the dip angle of pre-exciting crack, water pressure and crack width. The fracture toughness is most easily achieved when the dip angle of pre-exciting crack is 60°. The mode II stress intensity factor is symmetrically distributed with the dip angle and independent of the water pressure and crack width. For open-type crack, the crack initiation angle decreases with the increase of the dip angle of pre-exciting crack, water pressure and crack width;the crack initiation strength is inversely proportional to the water pressure and proportional to the lateral pressure. The research results can provide ideas for the study of crack initiation under the coupling of ground stress and osmotic pressure in tunnel engineering.