Abstract:
In order to study the settlement laws of soil mass around the metro tunnel in loess area with different pat? terns of deformations caused by collapse, a model test device, which consists of a model box, a flow rate control system and a settlement measurement system, is developed to measure loess settlements under even and uneven collapse modes. The collapse induced deformation of loess upon encountering water is summarized by indoor test, and the deformation law of tunnel surrounding rocks in loess area under two different submerging modes is analyzed. The experiment results show that the final accumulated settlements under uneven collapse is greater than that under even collapse, it means the uneven collapse causes more damages to the metro tunnel; the settlements near tunnel center line are the largest under the two types of collapse induced deformations, therefore, the monitoring of displacement at central line should be emphasized during construction. The influence of even and uneven collapse on the deformation of metro tunnel is analyzed by indoor model test. The research results are of great significance to the construction control and disaster avoidance during the tunnel construction in loess area.