Method for measuring moisture content or suction distribution of soil surface layer by using infrared thermal imaging technology

The invention discloses a method for measuring water content or suction distribution of a soil surface layer by using an infrared thermal imaging technology, and belongs to the crossing field of geotechnical engineering and environmental engineering. The method for measuring the surface layer suction of the soil body comprises the following steps: firstly, obtaining a relation calibration formula between the surface layer water content and the interface temperature difference in the soil body evaporation process, acquiring an in-situ soil body surface layer temperature field by utilizing an infrared thermal imager, and inverting a soil body surface layer water content field; calibrating a soil-water characteristic curve of the test soil body, determining the relationship between the suction force and the water content of the soil body, further obtaining the suction force of the specific position of the soil body surface layer at any moment, and inverting the suction force field of the soil body surface layer.