科研之友
微信
新浪微博
Facebook
分享链接
摘要
To investigate the action mechanism of anti-dislocation design parameters of a tunnel with flexible joint, the effects of the parameters of 'articulated design' on the damage pattern and anti-faulting mechanism of a tunnel are investigated by small-scale physical model tests, such as the lining segment length, the lining thickness, the tunnel diameter, the angle between the tunnel and the fault zone, and the lining cross-section type. The model test results are compared with the small-scale numerical analysis results to verify the correctness of the numerical simulations. The full-scale numerical model is applied to analyze the effects of the 'articulated design' parameters on the internal force response of a tunnel, such as the fault width, the flexible joint width and the stiffness of the flexible joint material. The results of the study show: (1) The damage characteristics of a tunnel with flexible joint are mainly exhibited with the failure of the flexible joints in the fault zone, the rotation between the lining segments under the dislocation of the strike-slip fault zone and S-shaped deformation of the tunnel in the longitudinal direction. In a few cases, the tunnel presents compression-shear damage of the lining segments. (2) The deformation of a tunnel with flexible joint is mainly concentrated in the fault zone. At the junction of the two walls and the fault zone, the left wall of the active plate is in tension and the right wall of the active plate is in compression; The left wall of the fixed plate is in compression and the right wall of the fixed is in tension. (3) The lining internal force in the fault zone appears saw tooth variation, while there is an obvious drop at the flexible joints. It can be concluded that the lining is in center-symmetric bending state, and that the position of the maximum moment is found at the boundary of the rock mass and the fault zone. while the maximum shear force occurs in the central of the fault zone. (4) In the aspect of the action mechanism of the design parameters of the tunnel with flexible joint, this paper concludes that increasing the tunnel thickness, decreasing the lining segment length or reducing the diameter of the tunnel can improve anti-faulting performance of a tunnel. The circular lining cross-section can improve the anti-faulting ability of a tunnel with flexible joint compared with the horseshoe lining cross-section, and the best angle of the tunnel through the fault zone is 90o. The wider fault zone, smaller deformation joint width, and less stiffness of flexible joint materials within a reasonable range make a tunnel with flexible joint safer under strike-slip fault dislocation.
- 单位
