JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

Numerical investigation of the effect of cross-sectional area and stress intensity on the development of damage zone around tunnels in hard rock mass

Document Type : Original Article

Authors
Faculty of Engineering, Tarbiat Modares University, Tehran, Iran.
Abstract

Increasing the depth of underground excavations in hard rock mass causes a strong reaction to excavation in this type of rock mass. An example of this reaction is the development of a damage zone around the excavation. In this study, the damage zone was modeled using two-dimensional numerical modeling in combination with a behavioral model of adhesion weakening and friction angle strengthening. The effect of cross-sectional area and stress intensity on the development of this zone was investigated. The results show a significant effect of the type of cross-sectional area with flat or curved surfaces. Flat surfaces create a damage zone with a higher concentration and depth. The direction of damage development is highly dependent on the stress intensity and the ratio of horizontal to vertical stress. Anisotropic stress field also causes the damage zone to develop in a specific direction.
Keywords

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