Cover-excavation top-down side wall construction joint waterproof structure

A cover and excavation top-down side wall construction joint waterproof structure comprises an enclosure structure, a main body structure and a waterproof structure, the main body structure comprises a top plate structure and a side wall structure, the side wall structure comprises a first construction side wall and a second construction side wall, and the waterproof structure is arranged in the range of a construction joint. Comprising a water seepage path extending convex body, a water swelling strip, a water stopping steel plate, a pressure grouting layer and an anti-seepage coating layer, the water seepage path extending convex body is arranged on the bottom face of a first construction side wall, the water swelling strip, the water stopping steel plate and the pressure grouting layer are all arranged in a construction joint, and the anti-seepage coating layer is sprayed on the surface of the construction joint of the downstream face. According to the waterproof structure, a plurality of defensive lines a