JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

Study of failure of closed non-extension plane and stepped joints using PFC2D software

Document Type : Original Article

Authors
1 Department of Mining Engineering, University of Sistan and Baluchestan, Zahedan, Iran.
2 Department of Mining Engineering, Hamedan University of Technology, Hamedan, Iran.
Abstract
In this paper, the shear behavior of closed planar and stepped joints has been studied using PFC2D software. For this purpose, a model with dimensions of 150 × 150 mm was created in the software environment. Then, calibrated microparameters were applied to the model. In order to investigate the effect of closed joints on the failure mechanism, the smooth joint model was selected in the software. Direct shear tests have been performed on two sets of models with pre-created joints in the form of level and stepped joints and a vertical stress of 0.1 MPa. The lengths of the joints created in the models are 2, 4, and 6 cm, and the vertical distance between the joints in the stepped state is considered to be 5 cm. The results show that the failure mode and failure pattern are a function of the longitudinal and transverse spacing of the joints. First, failure occurs in the rock bridge and then the closed joint is sheared. As the joint length increases, the shear strength of the joint decreases. As the angle of the stone bridge increases, the tensile strength decreases.
Keywords

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