Abstract: For solving the deficiency of triaxial apparatus of frozen soil in matching the real-time scanning of medical CT in the low temperature environment, a new triaxial apparatus of frozen soils is developed successfully. The configuration of the apparatus and the technical difficulties that need to be overcome in the development process are also introduced. The apparatus can be used to complete the triaxial loading and unloading test in the low temperature environment. Meanwhile, the medical CT matched with the newly developed apparatus can realize the real-time dynamic scanning in the whole mechanical process. On this basis, the real-time CT scanning test of frozen loess under triaxial loading is conducted. The test results show that the parameters of the newly developed apparatus can meet the real-time CT scanning conditions of the frozen soil samples under triaxial loading and unloading. In addition, the high quality mesoscopic CT images of different load conditions are obtained; and then the test results are also analyzed and discussed. The development of the apparatus has provided a new technical means for establishing the relationship between the mesostructure and the macroscopic mechanical properties.

Key words: frozen soil, CT scanning, apparatus, real-time loading, mesostructure change