Rheological effects of deep foundation pits near metro tunnels

The time-dependent properties of Shanghai soft soils under different loadings are studied based on indoor creep tests. The tests show that the creep curve can be simulated by means of the viscoelastic model which is composed of five elements when the loading is below a certain load limit. The creep effects of deep foundation pits are analyzed by using the viscoelastic model. The incline change of support construction by the excavation, the creep rate and non-uniform settlement of the metro tunnel are compared with the measured data. The results show that the viscoelastic model with of five elements can reflect the creep effects of deep foundation pits.