Discontinuities constitute an integral part of rock mass and inherently affect its anisotropic deformation behavior.This work focuses on the equivalent elastic deformation of rock mass with multiple persistent joint s...Discontinuities constitute an integral part of rock mass and inherently affect its anisotropic deformation behavior.This work focuses on the equivalent elastic deformation of rock mass with multiple persistent joint sets.A new method based on the space geometric and mechanical properties of the modified crack tensor is proposed,providing an analytical solution for the equivalent elastic compliance tensor of rock mass.A series of experiments validate the capability of the compliance tensor to accurately represent the deformation of rock mass with multiple persistent joint sets,based on conditions set by the basic hypothesis.The spatially varying rules of the equivalent elastic parameters of rock mass with a single joint set are analyzed to reveal the universal law of the stratified rock mass.展开更多
To investigate the influence of different joint conditions on the rockburst of a circular tunnel,a true-triaxial test of rockburst with a single set of joint conditions was conducted.The rockburst incubation and evolu...To investigate the influence of different joint conditions on the rockburst of a circular tunnel,a true-triaxial test of rockburst with a single set of joint conditions was conducted.The rockburst incubation and evolution characteristics and acoustic emission evolution characteristics under different joint directions and joint dip angles were studied.The Weibull function was used to fit rockburst debris with different particle sizes and a single set of joints to obtain statistical results.The experimental results revealed that shear fracture rockburst occurred in samples with joints aligned with the tunnel strike as well as joints with inclination angles of 45°,60°,and 90°.Slab buckling–shear fracture rockburst was more likely to occur in samples with inclination angles of 0°and 30°.Slab buckling–shear fracture rockburst occurred in samples with joints crossing the tunnel strike as well as in samples with joints with inclination angles of 0°,30°,45°,60°,and 90°.The location of the rockburst pit was influenced by the joint inclination angle when the joints aligned with the tunnel strike.In contrast,when the joints crossed the tunnel strike,the location of the rockburst pit was independent of the joint inclination angle.The cumulative absolute energy of acoustic emission(AE)exhibited an overall upward trend with the increase in joint dip angle.The cumulative absolute energy of the AE of the jointed samples was greater than that of intact samples(without joints).Loading reached the rockburst stage in the samples with joints aligned with the tunnel strike and dip angles of 45°,60°,and 90°.Moreover,the peak value of AE cumulative absolute energy was the highest.These results can elucidate the evolution mechanism of rockburst in the surrounding rock of circular tunnels with a single set of joints in deep underground engineering.展开更多
If you are representing a foreign-funded institution in setting up a foreign-funded bank or financial company in Shanghai, you should have a representative agency already established within the boundaries of China for...If you are representing a foreign-funded institution in setting up a foreign-funded bank or financial company in Shanghai, you should have a representative agency already established within the boundaries of China for more than two years, and general assets at the end of the previous year should not be less than US $ 10 billion. The country or region you are residing in should have展开更多
基金Projects(41172284,51379202) supported by the National Natural Science Foundation of ChinaProject(2013CB036405) supported by the National Basic Research Program of ChinaProject(2013BAB02B01) supported by the National Key Technologies R&D Program of China
文摘Discontinuities constitute an integral part of rock mass and inherently affect its anisotropic deformation behavior.This work focuses on the equivalent elastic deformation of rock mass with multiple persistent joint sets.A new method based on the space geometric and mechanical properties of the modified crack tensor is proposed,providing an analytical solution for the equivalent elastic compliance tensor of rock mass.A series of experiments validate the capability of the compliance tensor to accurately represent the deformation of rock mass with multiple persistent joint sets,based on conditions set by the basic hypothesis.The spatially varying rules of the equivalent elastic parameters of rock mass with a single joint set are analyzed to reveal the universal law of the stratified rock mass.
基金funded by the National Natural Science Foundation of China(Grant Nos.52364005,51934003)Yunnan major scientific and technological special project(202202AG050014).This support is gratefully acknowledged.
文摘To investigate the influence of different joint conditions on the rockburst of a circular tunnel,a true-triaxial test of rockburst with a single set of joint conditions was conducted.The rockburst incubation and evolution characteristics and acoustic emission evolution characteristics under different joint directions and joint dip angles were studied.The Weibull function was used to fit rockburst debris with different particle sizes and a single set of joints to obtain statistical results.The experimental results revealed that shear fracture rockburst occurred in samples with joints aligned with the tunnel strike as well as joints with inclination angles of 45°,60°,and 90°.Slab buckling–shear fracture rockburst was more likely to occur in samples with inclination angles of 0°and 30°.Slab buckling–shear fracture rockburst occurred in samples with joints crossing the tunnel strike as well as in samples with joints with inclination angles of 0°,30°,45°,60°,and 90°.The location of the rockburst pit was influenced by the joint inclination angle when the joints aligned with the tunnel strike.In contrast,when the joints crossed the tunnel strike,the location of the rockburst pit was independent of the joint inclination angle.The cumulative absolute energy of acoustic emission(AE)exhibited an overall upward trend with the increase in joint dip angle.The cumulative absolute energy of the AE of the jointed samples was greater than that of intact samples(without joints).Loading reached the rockburst stage in the samples with joints aligned with the tunnel strike and dip angles of 45°,60°,and 90°.Moreover,the peak value of AE cumulative absolute energy was the highest.These results can elucidate the evolution mechanism of rockburst in the surrounding rock of circular tunnels with a single set of joints in deep underground engineering.
文摘If you are representing a foreign-funded institution in setting up a foreign-funded bank or financial company in Shanghai, you should have a representative agency already established within the boundaries of China for more than two years, and general assets at the end of the previous year should not be less than US $ 10 billion. The country or region you are residing in should have
