Double-O-Tube Shield Tunneling-Induced Soil Displacement Considering Burial Depth and Convergence Mode: Transparent Soil Experiment and DEM Simulation

Double-O-tube shield tunneling technology has gained extensive attention due to saving space and the high cost-effectiveness of underground construction method. Estimating predicting DOT tunneling-induced soil displacements is essential prevent damage nearby aboveground structures in densely populated urban areas. This study develops a device for modeling based on transparent image processing technique investigates displacement during process tunnel, which considered uniform convergence mode (UCM) loss. Meanwhile, under non-uniform (NCM) analyzed contrastively using two-dimension particle flow code (PFC2D). The results show that horizontal increase gradually when tail passes monitoring face, while settlements rapidly. maximum surface settlement NCM are slightly larger than those UCM. A trapezoid-shaped failure pattern experienced at three tunnel depths. 1.93, 2.10, 2.05 times, respectively, as much UCM, corresponding H/D (the ratio depth diameter) = 1.0, 1.5, 2.0. arch effect above tunnels arises increases. Moreover, experimental numerical adopted assess validity proposed model, indicates model close test disturbance zone tunnels.