Study on Mechanism of Frost Heaving and Thawing in Construction of Tunnel-Channel Freezing Method

Artificial soil freezing technique is a well-proven soil improvement approach used worldwide to construct tunnels and many other civil structures in difficult subsoil or ambient conditions. We present quantitatively mechanism and the analyzing results from the applications monitoring of artificial soil freezing in tunnel construction projects. The interpretation of the field measurements is based on coupled computation simulations using the Abacus software for the freezing simulation analysis where the emphasis was on a realistic simulation of the overall project situation during the frozen body growth stage. The case study relates to a platform tunnel in a station of Hangzhou with the aims to determine missing but relevant material parameters via back analysis and to make comparisons of model predictions with field measurements and considerable construction delays occurred due to the inability to create a completely closed frozen body. Field monitoring and modeling activities to enhance our understanding of the mechanical integrity of freeze wall containment system will also be briefly introduced.