Permeameter for detecting soil permeability

The utility model discloses a permeameter for soil permeability detection. A stepped hole is formed in the chassis; the bottom of the sample cup is mounted in the stepped hole in a matched manner; a water injection pipe for injecting water into the sample cup is arranged on the side wall of the chassis; a pressing plate is slidingly matched with the top of the sample cup; a drainage cavity is formed in the pressing plate; a plurality of drainage holes communicated with the cavity of the sample cup are formed in the bottom of the drainage cavity; a drain pipe, an exhaust pipe and a positioningsleeve are arranged at the top of the pressing plate; the drainage pipe and the exhaust pipe are both communicated with the drainage cavity, the exhaust pipe is located on one side of the drainage pipe, the positioning sleeve is arranged in the middle of the pressing plate, a piston rod of the air cylinder is slidably matched in the positioning sleeve, a pressure detection head is arranged betweenthe piston rod of the air