Model test on water gushing characteristics of tunnel in water-rich fault(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2017年05期
- Page:
- 73-80
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Model test on water gushing characteristics of tunnel in water-rich fault
- Author(s):
- WU Hao; YANG Xiao-hua; CHEN Xing-yu
- 1. School of Highway, Chang’an University, Xi’an 710064, Shaanxi, China; 2. Broadvision Engineering Consultants, Kunming 650011, Yunnan, China
- Keywords:
- tunnel engineering; model test; water-rich fault; water gushing; numerical simulation; anti-burst layer
- PACS:
- U451
- DOI:
- -
- Abstract:
- In order to explore and research the change features of safety thickness of tunnel face, inflow of water and water pressures under various working conditions in the process of tunnel crossing the water-rich fault fracture zone, this paper researched the change law of measured values under three working conditions of no surface water supplying without grouting, surface water supplying without grouting and surface water supplying with grouting by means of model test and numerical simulation. A model test system was designed in the model test with a size similarity ratio of 1:80 on the basis of actual working conditions, including seepage system, water control system, measurement system and grouting system. The similarity relation of each physical and mechanical parameter was determined by the dimensional analysis method, and water gushing characteristics of the tunnel under the action of gravity field; length of the numerical simulation area were 240, 48 and 160 m in the X, Y and Z directions, respectively. The tunnel depth was about 80 m, the ordinary rock was Ⅴ grade and the fault fracture zone was Ⅵ grade. The results show that surface water supply can significantly increase the possibility of tunnel water gushing. In the model test, tunnel water inflow with surface water supply increases by 128.6% compared to that without surface water supply, and the safety thickness of tunnel face increases by 6 times. The pre-filled slurry method can improve the water gushing situation during the construction process in a certain range, while the water inflow cannot be reduced to a normal range, so other necessary measures should be taken. The pore water pressure in the surrounding rock displays a cone of depression distribution with tunnel as the axis. Water inflow and catastrophe point of water pressure value are the critical safety thickness of tunnel face. To ensure the construction safety, the safety thickness of tunnel face is recommended to be 0.8 to 1.6 m for no surface water supply without grouting, 2.4 to 4.8 m for surface water supply without grouting and 1.6 to 3.2 m for surface water supply with grouting.
Last Update: 2017-10-16