|
|
|
| Development and application of catastrophic experiment system for water inrush in surrounding rock of deep tunnels |
| JING Hongwen, YU Liyuan*, SU Haijian, GU Jincai, YIN Qian
|
| State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China |
|
|
|
|
Abstract Taking the strong concealment of seepage pressure along the water channel in inrush water disaster of deep buried rock as the background, based on the ideal generalizability of stress state of the anti-water-inrush rock mass, a large scale physical simulation test system for inrush water with high pressure and large flow was developed. The model size of this system was 1 800 mm×300 mm×300 mm. By using the plug-type uniform pressure servo loader, the geostress with the range of 0~6 MPa could be imposed on the model boundary, which could effectively reduce the negative effects induced by uneven loading and stiffness mismatch on the test results. The high pressure water source(2 MPa)was composed of a group of high pressure nitrogen tanks and a water irrigation system with large capacity constant pressure. Due to high sensitive characteristics of gas and liquid composite loading, both large flow recharge and high water pressure maintenance after catastrophe could be realized. A complete set of testing technology, including similar materials, model placement, and data acquisition, had been developed. A “four-in-one” boundary water proof method of “water proof cement+waterborne polyurethane+epoxy resin+auxiliary water proof belt” had been proposed, from which, the problem of high pressure water seal on the boundary of similar material was effectively solved. Then, a series of indoor tests on the typical disaster induced structures, with respect to various geological defects of different formation and scale, in-situ stress level and direction, water inrush pressure, as well as the filling medium characteristics, were conducted. Combined with the multi-field coupling numerical simulation, a spatio-temporal evolution theory model of seepage pressure and hydraulic gradient along the water channel was put forward. The inherent mechanism of progressive inrush channel conduction was preliminarily revealed.
|
|
Received: 26 April 2018
Published: 22 February 2019
|
|
|
|
|
|
|
|
