Temporal and spatial variation of temperature and displacement fields throughout cross-passage artificial ground freezing

The artificial ground freezing (AGF) method exhibits advantages of non-pollution, a good effect of reinforcement, and water sealing that are widely applied in underground engineering. However, the AGF method would disturb the original ground stress field and cause frost heave and thaw settlement. Therefore, it is significant to study the development of temperature and displacement fields for better and more efficient application of the AGF method. In this paper, a complex three-dimensional model, which considers the deflection arrangement of freezing pipes, the ice-water phase change, the thermal-mechanical coupling, and the nonlinear change of soil parameters comprehensively, has been created to study the temperature and displacement variations throughout the entire construction period of a representative AGF project. The findings demonstrate that the proposed sophisticated model corresponds well with the field monitoring results, which meet the limit value required by the specification. It is determined that each AGF construction period must be taken into account in order to more accurately estimate the freezing effects and environmental influences throughout the AGF project. •A method to study the entire AGF process, including active freezing, maintenance freezing, and natural thawing period.•A sophisticated three-dimensional model considering thermal-mechanical coupling is established.•Both the temperature and displacement numerical values are in good agreement with the corresponding measured results.•The cross-passage excavation and the ice-water phase change both significantly affect the AGF process.