Underwater surface soil penetration strength testing device

The utility model relates to an underwater surface soil body penetration strength testing device which comprises a pressure cylinder placed on the surface of an underwater soil body, a sealing plate which is in sealing fit with the inner wall of the pressure cylinder and can slide up and down relative to the pressure cylinder is arranged in an inner cavity of the pressure cylinder, and the lower side of the sealing plate is fixedly connected with a testing rod extending downwards. The lower end of the pressure cylinder is provided with a bottom hole which allows the lower end of the test rod to penetrate through and is in sealing sliding fit with the pressure cylinder, an annular copper electrode is embedded in the upper end of the pressure cylinder, and an electrode bar extending upwards is fixedly connected to the upper end of the sealing plate, penetrates through the middle of the copper electrode and is in sealing sliding fit with the copper electrode. A plurality of electrode plates matched with the copp