Gas breakthrough pressure test device and method

The present invention discloses a gas breakthrough pressure test device, and relates to the field of high-level waste disposal technologies. The test device comprises a cylinder body configured to contain a sample, a sealing section is molded at the inner wall of the cylinder body, one end of the cylinder body is a gas inlet end, the other end of the cylinder body is a gas outlet end, the gas inlet end is connected with a gas transmission device, and the gas outlet end is connected with a gas monitoring device. According to the gas breakthrough pressure test device, the sealing section is processed at the inner wall of the cylinder body, for a sample with expansibility, after water absorption, the sample is expanded to block the sealing section to achieve sealing, and therefore, the sampleand the cylinder body cannot be a smooth contact surface in a vertical direction, it is avoided that gas is broken through from a boundary surface of the sample and the cylinder body and accuracy ofa gas breakthrough pressur