Instrument for accurately measuring thickness of sediment at bottom of cast-in-place pile

The utility model relates to the technical field of building construction measurement, and provides an instrument for accurately measuring the thickness of sediment at the bottom of a cast-in-place pile, which comprises a hanging cake capable of floating on the surface of the sediment, a hanging hammer capable of sinking into the bottom of a hole and a sleeve used for supporting the hanging hammer, the lifting rope is provided with first scales through which the thickness of sediment can be obtained. According to the instrument for accurately measuring the thickness of the sediment at the pile bottom of the cast-in-place pile, before a drilled hole reaches the designed depth and concrete is poured, the lifting rope is lifted by hands, the instrument is put down into a pile hole, the disc on the instrument falls on the top face of the sediment and keeps stable, and the drop-hammer can accurately measure the thickness of the sediment under the self-weight effect. The auxiliary buckle with the lifting rope is pu