Underwater test platform for hydraulic pile hammer

The invention discloses an underwater test platform for a hydraulic pile hammer; the test platform comprises a foundation pit, spring damping vibration isolators and water baffles, the bottom wall of the foundation pit is provided with a plurality of groups of uniformly arranged spring damping vibration isolators, the outer walls of the spring damping vibration isolators are provided with the water baffles, and the tops of the spring damping vibration isolators are provided with platform bases; a height adjusting structure is installed on the top of the platform base and composed of a circular truncated cone, an expansion plate, an electric telescopic rod, an outer cover cylinder and an annular protruding block, and the bottom of the circular truncated cone is attached to the top of the platform base. The height of the platform can be changed when the platform is used, so that the hydraulic pile hammer with different height specifications can be conveniently tested through the platform, the installation betwe