Building waterproof structure of novel expansion joint

The building waterproof structure comprises a building block, an expansion joint body penetrates through the middle of the building block, a connecting block is perpendicularly and fixedly connected to the middle of the inner wall of the expansion joint body, a right supporting wall and a left supporting wall are connected to the connecting block through fastening bolts, and a rotating block is fixedly connected to the lower end of the side wall of the left supporting wall; the rotating block penetrates through the right supporting wall to form a rotating groove, a plug pin penetrates through the middle of the rotating block and the middle of the rotating groove and rotates in the rotating groove, the upper end of the inner wall of the expansion joint body penetrates through a connecting groove, the connecting groove is connected to the supporting block through a connecting bolt, and the extending end of the supporting block penetrates through and is slidably connected with a sliding block. The right supporti