Creep behavior of frozen soil and creep analytical model of frozen wall.

Abstract

Taking the Gubei Mine as the research object, indoor uniaxial creep tests were carried out at temperatures of -5, -10, and -15℃ under loads of 0.3, 0.5, and 0.7σs to study the creep characteristics of deep soil, Based on the Burgers rheological model and the auxiliary formula of viscoelastic rheological formula, the freezing pressure under the combined action mechanism of frozen wall, outer shaft wall and polystyrene foam board was theoretically analyzed. The results show that the creep deformation of frozen clay under a certain constant stress loading changes with time. At three temperatures, the creep is attenuated creep under constant stress of 0.3 and 0.5σs; it exhibits non-attenuated creep at a constant stress level of 0.7σs, and the growth rate increases over a certain period of time, and finally it is destroyed by excessive deformation over time. The calculated value of the freezing pressure calculated by the frozen wall model is roughly the same as the development law of the measured value, and the calculated value of the theoretical value of the freezing pressure is slightly larger than the measured value, indicating that the calculated value can be an effective reference for the creep of the frozen wall and can provide a guarantee for the construction safety.