A Model Study of Water Inrush in Underground Roadways

Abstract

Groundwater is one of the key problems that must be faced and solved in underground engineering. Under special conditions, large-scale water damage accidents will occur. Therefore, it is of great engineering significance to study the stability of the surrounding rock of water-inrush roadways. In this paper, a laboratory model test is used to simulate the actual project. First, similar material and the similarity ratio of the test are determined, and the relationship between the ratio of the similar material and its physical parameters is analyzed through an orthogonal test, the multiple linear regression equation of the two is established, and the optimal ratio of the model similar material is determined. Then, the model test of tunnel water inrush is carried out. Through the orthogonal test, the influence of roadway depth, water-inrush height and water-inrush time on the stability of surrounding rock during and after tunnel water inrush is analyzed, and the numerical simulation is used to verify and extend the conclusion. The test results show that the sensitivity of each factor to roadway stability is as follows: water-inrush height > water-inrush time > roadway depth. In the test within 24 h after water inrush (7 days in actual engineering), the sensitivity of each factor to roadway stability is also water-inrush height > water-inrush time > roadway depth. This conclusion can provide an important basis for the rescue work after tunnel water inrush and enrich the relevant test simulation after tunnel water inrush. In this paper, a laboratory modeling test is used to emulate the actual project where groundwater exists. Similar materials used in the model test and their optimal ratios are determined by similarity ratios and multiple linear regression equations. The effects of roadway depth, water-inrush height, and water-inrush time on the stability of the tunnel’s surrounding rock are investigated by orthogonal tests, and finally the results are verified by numerical simulation. The test results show that the sensitivity of each factor to the stability of the roadbed is as follows: water-inrush height > water-inrush time > roadway depth. In the test within 24 h after water influx (7 days in the actual project), the sensitivity of each factor to the stability of the tunnel is also water-inrush height > water-inrush time > roadway depth. This conclusion can provide an important basis for the rescue work after the tunnel water influx and can provide suggestions for the early reinforcement support of the project in the presence of groundwater.