XU Ming, YUAN Bang-guo, CAI Yu, et al. Analysis of stress concentration characteristics at rock joint ends under stress wave disturbance[J]. 2025, 46(6): 1687-1699.
XU Ming, YUAN Bang-guo, CAI Yu, et al. Analysis of stress concentration characteristics at rock joint ends under stress wave disturbance[J]. 2025, 46(6): 1687-1699.DOI: 10.16285/j.rsm.2024.1056.
To analyze the stress concentration effect at rock joint ends under dynamic disturbance
a modified hyperbolic model of non-uniform joint normal stiffness distribution is introduced
based on the compression closure and elliptical shape characteristics of rock joints. Factors such as in-situ stress
joint inclination angle
and joint length are considered to compare and analyze joint surface stress and end stress concentration effect under P wave and SV wave disturbances. Results indicate that considering joint morphology
the closer to the joint ends
the greater the disturbance amplitude of the stress wave on the joint surface’s normal stress
and the reduction effect of joint on the stress wave diminishes
resembling the propagation effect in intact rock. The stress concentration effect at the joint ends is positively correlated with the compressive stress and shear stress on the joint surface
but the stress concentration effect at the joint end caused by compressive stress is more significant. Considering the characteristics of joint morphology
the fluctuation of stress concentration effect at the end with the incidence of stress wave is more obvious than that of ignoring the joint morphology
increasing the likelihood of damage. Therefore
considering the joint morphology is more conducive to the analysis of engineering safety. Under the same conditions
P wave primarily causes the change of normal stress on the joint surface
while SV wave primarily causes the change of shear stress. Analysis of the joint end extension point shows that as the incident angle of the stress wave increases
the effect of SV wave on the shear stress at the monitoring point weakens
while its effect on normal stress strengthens
opposite to the effect of P wave. The horizontal displacement is positively correlated with the normal stress value
and the vertical displacement increases with the increase of the shear stress. When the joint experiences tensile shear stress
normal stress in most end areas is tensile
whereas it is primarily compressive in the compressive shear state.