Abstract:

The control standard of the deformation of foundation pits is a given value. I f the measured value is lower than the above-mentioned given value, it is believed that the project is safe and that no harmful impact will be imposed to the environment; otherwise, it is believed that the construction of the project will do harm to the surrounding environment. The following proposal is made on the control standard of the deformation of the foundation pit of Tianjin Station on basis of the characteristics of the foundation pit and the requirements on the environment control: the proposed control standard for the ground surface settlement is 30~50mm; the proposed control standard for the horizontal displacement of the retaining structure is 60~75mm; the proposed control standard for the internal force of the support is 0.65f and the proposed control standard for the earth pressure is 0.6~0.7f ("f " is the axial force or the designed load value). The study results can provide reference for the determination of the control standard for similar projects in the future.

Key words: super-deep foundation pit, ground surface settlement, retaining structure, control standard