... flexure module 5900 MPa1. The roof, 2.the blowhole, 3.the tension bar, 4.inside jotting board, 5. The manhole cover, 6.inside ladder, 7 ... by your side), 13.The steel frame, 14. The drainage outlet.15. The drainage board, 16.The bottom board, 17.The outside jotting board, 18.the side board