Soil column device and method for measuring gas permeation and diffusion coefficients of unsaturated soil body

The invention provides a soil column device and method for measuring gas permeation and diffusion coefficients of an unsaturated soil body. The soil column device comprises a gas supply device, a measuring device, a tail gas treatment device and a data acquisition device, the measuring device comprises a cylindrical container; a plurality of soil samples are loaded in the inner cavity of the cylindrical container in a layered manner; a sensor assembly connected with the data acquisition device is arranged at an interface between each two layers of soil samples; the bottom of the cylindrical container is communicated with the gas supply device through an air inlet valve; according to the technical scheme, the gas permeation and diffusion coefficients of the soil sample under different watercontents and suction forces can be obtained only by obtaining the gas pressure and the tracer gas concentration of the measuring point and the adjacent point and substituting the gas pressure and thetracer gas concentration