Creep behavior of ice-soil retaining structure during shaft sinking

摘要

The article is devoted to analysis of deformation of an ice-soil retaining structure during a vertical mine shaft sinking by applying the artificial ground freezing technique. The analysis was performed by finite element numerical simulation. Since frozen soils possess rheological properties, creep deformation of the ice-soil structure was considered. To determine the creep deformation, the Vaylov's constitutive relations was used. In the relations the creep behavior is described by the Norton-Bailey creep law and the volumetric creep strain is restricted to be zero. The wall thickness of the ice-soil structure was estimated by the Vaylov's formula that is widely used in structural design of potash mines. As a result of the study, it was established that for time required for the lining installation at large depths of the shaft sinking the creep deformation of the ice-soil structure exceeds admissible value guaranteeing safety of the excavation process.