Device and method for in situ penetration measurement of gas transport parameters in unsaturated soil layer

A device for in situ penetration measurement of gas transport parameters in an unsaturated soil layer, comprising:

• a gas supply system, a gas concentration display recorder, a gas pressure display recorder, a sleeve, a gas concentration sensor, a gas pressure sensor, a porous gas-permeable tube, and a conical penetration head, wherein a top portion of the porous gas-permeable tube is connected to a bottom portion of the sleeve through a thread, a bottom portion of the porous gas-permeable tube is connected to the conical penetration head through a thread, an inner portion of the porous gas-permeable tube is filled with sand grains, the gas supply system comprises a high-purity inert gas cylinder, a high-pressure air cylinder, a small-flow pressure regulating valve, a large-flow pressure regulating valve, a small-scale air gauge, a large-scale air gauge, a small-scale mass flow controller, a large-scale mass flow controller, and a gas pipeline, an output end of the high-purity inert gas cylinder is connected to one end of the gas pipeline through the small-flow pressure regulating valve, the small-scale air gauge, and the small-scale mass flow controller in sequence, an output end of the high-pressure air cylinder is also connected to one end of the gas pipeline through the large-flow pressure regulating valve, the large-scale air gauge, the large-scale mass flow controller in sequence, another end of the gas pipeline extends into and penetrates the sleeve and communicates with the porous gas-permeable tube at a bottom portion of the sleeve;
• the gas concentration sensor and the gas pressure sensor are installed in the inner portion of the porous gas-permeable tube, and the gas concentration sensor and the gas pressure sensor are respectively connected to the gas concentration display recorder outside the porous gas-permeable tube and the gas pressure display recorder through data lines thereof.