Intellectual monitoring of artificial ground freezing in the fluid-saturated rock mass

摘要

The paper is devoted to the development of monitoring system of artificial ground freezing process (ice wall formation) under vertical shaft sinking. The work consists of two parts. The practical part includes the development of real-time spatial distributed temperature monitoring system. The temperature in control boreholes is measured using fiber-optic system Silixa Ultima based on the Raman Effect. The fiber-optic system has a characteristic length of several hundred meters and measures the temperature with the step equaled to 0.25m and precision of 0.1°C. The monitoring system is coupled with thermo-hydro-mechanical model of fluid-saturated poroelastic media. This model is used for numerical simulation of freezing process. The model increases the possibilities of the current state control of the process and allows us to forecast the evolution of ice wall. To illustrate the efficiency of the developed system the examples of real monitoring of artificial ground freezing in the fluid-saturated rock mass and simulation of freezing and defrosting processes are presented.