摘要
The process of the change in the frozen wall can be divided into four stages, i. e. the pre-circumscribed circling, the active freezing, the keep （or inactive） freezing and the natural recovery periods. It is assumed that the frozen holes are distributed on the circumference of a circle with radius R0 and the center concurrent with the center of digging shaft. Having a discussion on the water content together with the thermal effect and considering
