The utility model relates to the technical field of piezometric tubes, and discloses a dam foundation piezometric tube orifice device which comprises a piezometric tube body, a transverse tube fixedly communicates with the piezometric tube body, a
vertical tube fixedly communicates with one end, away from the piezometric tube body, of the transverse tube, a faucet fixedly communicates with the upper end of the
vertical tube, an extension tube fixedly communicates with the
vertical tube, and the extension tube is fixedly communicated with a water outlet. A pressure gauge is fixedly installed at the end, away from the vertical
pipe, of the extension
pipe, an
osmometer is installed in the pressure measuring
pipe body, and a cable head is externally connected to the
osmometer. The structure of the pipe orifice device is simplified, the cost is reduced, the
measurement precision and the stable operation of the
system are improved, the height of any
water column in the
pressure measurement pipe can be measured, the stability and reliability of automatic measurement values can be calibrated, the
uplift pressure distribution condition of a dam foundation can be accurately mastered, and the working efficiency is improved. Materials are common and easy to purchase,
assembly and installation are easy, monitoring is convenient, manpower is saved, monitoring types are multiple, and checking is convenient.