As a common soil reinforcement method, artificial ground freezing method is widely used in underground structure engineering such as coal mine and subway. The sandy cobble stratum in Chengdu has rich water content and high permeability coefficient, where is difficult for freezing method. In this paper, the construction of cross passage by artificial freezing method in sandy cobble stratum was examined based on a tunnel section of Chengdu Metro Line 10. Firstly, the field monitoring of freezing engineering is carried out. Secondly, a nonlinear three-dimensional elastic-plastic thermal-stress coupled numerical model considering ice water phase transformation was established according to the actual layout of freezing pipes. The development and distribution of temperature field and displacement field in active freezing period were studied by field monitoring and numerical simulation. The research result shows that the numerical simulation results were in good agreement with the field monitoring data, and the established numerical model was reliable; the time of closure of freezing wall is critical for rapid growth of frost heave deformation, and the time is about 25 days; the thickness of frozen wall reached 2 m for freezing of 43.7 days, and the average temperature in the frozen wall reaches -10 ℃ in 37.8 days, which meets the requirements of subsequent excavation construction.