Impacts of confining pressure and safety thickness on water and mud inrush in weathered granite |
| |
| Authors: | Jinquan Liu Weizhong Chen Zhiping Deng Taogen Liu |
| |
| Institution: | 1. School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang, Jiangxi, China;2. Quanzhou Institute of Equipment Manufacturing, Haixi Institutes, Chinese Academy of Sciences, Quanzhou, Fujian, China;3. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics Chinese Academy of Sciences, Wuhan, Hubei, China;4. Nanchang Institute of Technology, Nanchang, China |
| |
| Abstract: | AbstractDue to the strong disintegration and water erosion of completely weathered granite, water and mud inrush disasters are apt to take place in this zone during underwater tunnel construction. The pore, compactness, seepage path length, fracture geometries and their interconnections for water and mud transfer are strongly influenced by confining pressure and waterproof-resistant slab safety thickness. In order to inspect the influence, a series of experiments based on a self-designed testing system and non-Darcy testing method were performed. The results indicated that the water and mud inrush evolution increased with the increase of confining pressure and decreased with the increase of safety thickness. In particular, the confining pressure mainly influences the initial evolution stage, and a critical safety thickness to prevent water and mud inrush is obtained. Besides, the non-Darcy testing method results shows that the water and mud inrush evolution affects the influence of non-Darcy flow. For example, while the safety thickness was smaller than the critical value, the evolution was large and unstable and its behavior transferred into nonlinear. In this case, the flow changed to non-Darcy flow. |
| |
| Keywords: | Mass transfer non-Darcy flow completely weathered granite water and mud inrush confining pressure safety thickness tunnel engineering |
|
|
