Backfill sampling device for project supervision

The invention discloses a backfill sampling device for project supervision. The sampling device comprises a sampling shell with an external in tapered structure arrangement, the internal of the sampling shell is a cylindrical sampling cavity, multiple guiding fixed columns are uniformly distributed on a device wall of the sampling shell, a pressing plate is arranged at upper parts of the guiding fixed columns, an upper part of the sampling shell is in threaded connection with a thrust cover, the thrust cover is movably connected with a push block, a threaded push rod is formed on the push rod,the threaded push rod is in threaded connection with the pressing plate, and an annular rotary handle is arranged at an end part of the threaded push rod; a material guiding port corresponding to thecylindrical sampling cavity is arranged at the end part of the sampling shell, an anti-backflow inner eave corresponding to the material guiding port is arranged at an inner side of the sampling shell, and a protective cover is arranged at a front end of the material guiding port, so that the fetching can be easier after the resampling and the sampling of the shell are accomplished, a metal rod cannot be remained in the middle of a soil sample, and the sampling stability can be increased; and the protective cover is provided for protecting the soil sample in time after the sampling is accomplished, and the falling of the soil sample can be reduced.