标题：Study on the Crack Growth Law and Mechanism of the Rock Mass with Defect Combination
作者：Yang W.; Wei B.; Xu Y.
作者机构：[Yang, W] State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Provence and the Ministry of Science and Technology, S 更多
通讯作者地址：[Wei, B] Dongtan Coal Mine of Yanzhou Coal Co. LTDChina;
来源：Geotechnical and Geological Engineering
关键词：Crack propagation; Different angles; Prefabricated defect combination; Stress concentration
摘要：There are different defect combinations in natural rock mass. In the process of underground engineering excavation, the existence of defect combination poses a serious threat to the construction safety. In this paper, the uniaxial compression test of red sandstone with prefabricated defects combination angles of 15°, 30°, 45°, 60° and 90° was conducted by Shimadzu universal testing machine respectively, and the crack propagation law and mechanism of red sandstone with different defects are studied, The test results showed that the red sandstone with different angle defects only produced tensile cracks, there had not shear cracks, and finally resulted in tensile failure. This was due to the existence of defects combination which weakened the local stress concentration and releases part of energy in advance. With the increasing of the defect combination angle, the weakening degree of stress concentration increased, and the uniaxial compressive strength of the specimen decreased as a whole, and with 45° as the boundary. There was an obvious strength area division, and the failure time of the specimen was obviously prolonged, furthermore, the brittle failure characteristics of specimens are obviously weakened. The test results have important guiding significance and reference value for the construction design in the field of underground engineering. © 2020, Springer Nature Switzerland AG.