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Based on the thermodynamic and thermoelastic theory, the coupled governing equations of deformation, heat transfer, and moisture migration in unsaturated soils were given. The coupled calculation process was realized by the finite element method. The hydrothermal coupling characteristics of two cases of unsaturated kaolin clay were studied by using a self-developed test device, and the test results were compared with the numerical results. The results showed that when the initial saturation of the soil is high, the volumetric water content of the measured point increases, and then it is in a stable state during the heating process. When the initial saturation is low, the volumetric water content near the heat source increases firstly and then decreases during the heating process. The rise and fall of temperature make the volumetric water content of the soil irreversible. The volumetric water content of each measured point is lower than the initial state. The closer it is to the internal measured heat source, the more obvious this phenomenon is; the lower the initial saturation is, the more obvious it is.

The sandy cobble ground has loose structure, uneven particle size, and random distribution characteristics, which may lead to the local collapse of ground. This paper carried out field tests based on the project of Luoyang urban rail transit. For this, the surface settlement, pore water pressure, and earth pressure in the test section were measured. The excavation disturbance and influence range on the soil layer in each stage of earth pressure balance shield tunneling were studied. Meanwhile, based on the key construction elements in sandy cobble ground, a numerical simulation method was proposed based on shield construction parameters. The disturbance characteristics of deformation, seepage action, and stress state of the sandy cobble ground during shield construction were obtained through numerical calculation. The rationality of the simulation results was verified by the measured tests. The results showed that the measured data were in good agreement with the simulation results. The research results provide a calculation method for predicting the soil disturbance in the earth pressure balance shield construction in a sandy cobble ground.