ABSTRACT
During shield tunneling in complex environments, instability at the excavation face can disturb existing structures, potentially leading to structural failure. To investigate the stress and displacement responses of both the soil and existing structures under such conditions, various types of existing structures are modeled to represent different complex scenarios. Settlements of the existing structures and surrounding earth pressures are measured, and soil motion patterns are analyzed using particle image velocimetry.
The results indicate that when an existing tunnel fails, the differential settlement of surface buildings increases significantly, surpassing that observed when the tunnel is in a stable condition. The findings highlight that structural failure amplifies the disturbance transmission, with the experimental tests revealing both the displacement behavior of the structures and the soil, as well as the cascade amplification effect.
