ZHENG Luo-bin, WANG Liang-qing, ZHU Lin-feng, et al. Experimental study on the effect of locking mode on shear characteristics of
bolted rock joint[J]. 2021, 42(4): 1056-1064.
ZHENG Luo-bin, WANG Liang-qing, ZHU Lin-feng, et al. Experimental study on the effect of locking mode on shear characteristics of
bolted rock joint[J]. 2021, 42(4): 1056-1064.DOI: 10.16285/j.rsm.2020.1050.
Rock bolts have been widely used as the reinforcement of jointed rock mass. To explore the shear behaviors of bolted rock joints
the influences of two locking modes
i.e.
two-end locking and no-locking
on the shear characteristics of bolted rock joints were studied based on the indoor direct shear tests. The enhancement of the shear strength of the bolted rock joints influenced by normal stress and prestress was analyzed. During the test
the variation laws of the axial forces at varying monitoring points of the bolt were recorded by strain gauges
and the axial force mechanism of the bolt under different locking modes was studied. The deformation characteristics of the bolt after shear test were carefully examined and the influence of normal stress on the bending deformation of the bolt was analyzed. The results show that the shear stress-displacement curves of the locking bolted joints at both ends can be divided into three stages
i.e.
the initial elastic stage
elastoplastic stage and plastic hardening stage. The shear stress-displacement curves of the unlocked bolted joints can be divided into three stages
i.e.
the initial elastic stage
elastoplastic stage and plastic softening stage. The locking mode has a significant impact on the shear strength and the axial deformation of bolt. Compared with the no-locking mode
the lock at both ends is more conducive to the shear resistance. Based on the analysis of the plastic hinge position of bolt after shear test
it shows that the normal stress has an important influence on the plastic hinge position
and the distance between the plastic hinge points decreases with the increase in the normal stress. Finally
an analytical model was proposed to predict the position of the plastic hinge. The new model takes into account the influence of the normal stress