Mechanical properties of rock mass structural plane under cyclic loading
Cyclic shear mechanical properties of rock discontinuities under dynamic cyclic seismic loads play an im-portant role in the safety and stability of engineering rock masses.In order to study the multi-factor coupling to the real structure,the Brazilian splitting method was used to obtain the real structure plane,while 3 D scanning and printing technology were adopted to make rock mass structural surface templates.In addition,reverse mould method was employed to make preparations in batch for shear specimens,and then the cyclic shear tests are carried out to research the effects of the normal pressure,the structure of the specimen strength and surface roughness on the me-chanical properties of structural plane shear.The experimental results show that:(1)With the increase of shear dis-placement,the shear stress increases in the initial stage of the first cycle and then decreases slowly.When crossing the origin,the shear stress begins to increase again.(2)Under different normal stresses,the maximum shear stress decreases with the increase of shear times,and the wear degree of specimens becomes more serious.(3)The shear stress increases with the increase of normal stress,specimen strength and roughness of structural plane.The research results can provide theoretical guidance for the parameter design of practical rock mass engineering.
rock discontinuitiescyclic shearingmechanical propertiesinfluencing factors