【摘要】 基于核磁共振技术,对大理岩三轴压缩作用下的裂隙发展规律进行分析,得到大理岩在10 MPa围压条件下的应力-应变曲线,不同轴压状态下岩石孔隙度及T2谱曲线,利用颗粒流程序对10MPa围压条件下的岩样裂隙形成过程进行追踪试验。研究结果表明:T2谱曲线能反映岩石内部裂隙发育过程,孔隙度随轴向应力增加呈指数形式增长。大理岩在三轴压缩低轴压阶段,岩石损伤以裂隙数增加为主要特征;高轴压条件下,岩石损伤主要由裂隙数增加及裂隙贯通引起。10MPa围压状态下的大理岩损伤度随岩石孔隙度、轴向应力的变化特征符合指数函数关系。更多还原

【Abstract】 Based on the nuclear magnetic resonance technology,the fracture development law of marble under the action of triaxial compression was analyzed,and the stress-strain curve of marble under the confining pressure of 10 MPa and the rock porosity and T2 spectrum curve under different axial compression were obtained.The process of fracture formation in rock samples under 10 MPa confining pressure was tracked by particle flow program.The results show that T2 spectrum curve truly reflects the process of fracture development in the rock,and porosity increases exponentially with the increase of axial stress.In the low axial compression stage of marble triaxial compression,the main inducement of rock damage is the increase of fracture number.Under high axial pressure,the damage of rock is mainly caused by the increase of the number of cracks and the penetration of cracks.The variation of marble damage degree with rock porosity and axial stress under 10 MPa confining pressure conforms to exponential function.更多还原