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为研究锚杆对多组有序裂隙岩体的作用机制,以水泥砂浆预制多组有序裂隙类岩体,采用玻璃纤维塑料筋材(GFRP)模拟锚杆,对预制的类岩体进行全长锚固,制作多组不同锚固条件下的试件。将预制试件在RMT-150伺服试验机进行单轴压缩破断试验。根据试验结果提出了主控裂纹的概念,认为主控裂纹的贯通导致了试件强度的弱化。分别从细观上研究了锚杆对多组有序裂隙类岩体主控裂纹的起裂、扩展和贯通影响机制;从宏观上研究锚杆对多组有序裂隙岩体峰值强度、残余强度以及抗变形能力的影响。研究发现:锚杆锚固后多组有序裂隙类岩体主控裂纹由纵向—倾斜—横向贯通为主的扩展、贯通模式转变为横向—纵向—倾斜的模式,主控裂纹路径更长且贯通过程受到锚杆锚固限制,具体表现为锚杆锚固改变了裂纹尖端的应力强度因子使得类岩体试件抗变形能力更大、试件的峰值强度和残余强度更高。但并非加锚密度越大,类岩体强度越高,适当的加锚密度才能获得更好的支护效果。
In order to study the mechanism of the bolt on the multi-group ordered fractured rock mass, a series of ordered fractured rock masses were prefabricated with cement mortar. The GFRP model was used to simulate the rock bolt. Long anchoring, making multiple sets of specimens under different anchoring conditions. Prefabricated specimens were uniaxial compression rupture test in RMT-150 servo testing machine. According to the test results, the concept of the master crack is proposed. It is considered that the crack propagation leads to the weakening of the specimen strength. The mechanism of initiation, propagation and penetration of anchor cracks in multiple groups of ordered fractured rock mass is investigated respectively from the perspective of macroscopic. The effects of rock bolt on the peak intensity, residual strength As well as anti-deformation ability. It is found that the dominant cracks in the groups of ordered fractured rock mass after anchored by anchors are mainly extended by the longitudinal-inclined-transverse penetrating mode, and the penetrating mode is changed to the transverse-longitudinal-inclined mode. The dominant crack path is longer and continuous The process is limited by the anchoring of anchors, which is characterized by that the stress intensity factor of anchoring the anchors changes the crack tip so that the deformation resistance of the specimens is greater and the peak strength and residual strength of the specimens are higher. But not the greater the anchor density, the higher the strength of the rock mass, the appropriate anchor density can get better support effect.