The shear behavior of inclined rock joint containing weak interlayers are closely related to the dip angle and degree of infill.To obtain the shearing characteristics of inclined rock joint with undulating morphologies containing weak interlayers,direct shear tests were conducted on samples of inclined rock joint with such morphologies using a multifunctional geotechnical contact-destruction testing system.The results show that the shear stress-shear displacement curves of inclined rock joint without weak interlayers exhibit peak shear fracture characteristics,while those containing weak interlayers show sliding failure characteristics.Under varying degrees of infill,the normal displacement of inclined rock joint increases with increased shear displacement,with the rate of change gradually increasing and stabilizing,showing a dilation effect.Under different dip angles,the normal displacement of rock joint with shear displacement,and the early growth rate of normal displacement is significantly less than the latter.The shear strength of inclined rock joint shows a negative exponential decrease with increasing degree of infill,an approximately linear increase with an increasing dip angle,and an approximate linear increase with increasing normal stress.Considering the impact of weak interlayer material,degree of infill,and dip angle on shear strength,a new model for shear strength suitable for inclined rock joint containing weak interlayers was established based on the Barton shear strength model.The research findings can provide a reference for evaluating the stability of engineering rock masses.
rock jointweak interlayerfilling degreedip angleshear propertiesdirect shear test