Abstract: Disclosed in the present disclosure is a double-deck multi-span bridge construction method. According to the double-deck bridge construction method of the present disclosure, construction is carried out by using a method of disassembling a support jig frame in a graded and span-separated mode, an upper chord jig frame and a lower chord jig frame can be used in a recycle manner, and construction costs are reduced. In addition, a construction period of building the support jig frame is shortened, and other construction operations can be synchronously carried out on a span in which the jig frame is disassembled, for example, fire retardant coating construction can be carried out on a mounted bridge deck after the jig frame is disassembled, and the construction period of a double-deck multi-span bridge is effectively shortened.

Abstract: The present disclosure relates to the technical field of production of H-shaped steel and discloses a production line of H-shaped steel and a production method. By arrangement of the assembly zone in which a welding line is arranged and the welding zone in which a welding line is arranged, a process layout of assembly and welding flow type machining production line can be formed. Assembly and welding of a stiffening plate are operated independently, and a carrying robot, a spot welding robot and a welding robot are movable between stations. A transfer device transfers an H-shaped workpiece in the process of feeding, machining and discharging, thereby implementing flow type machining, which can effectively improve machining efficiency. Through the production method, the assembly and welding flow type machining of the stiffening plate can be implemented, thereby effectively improving machining efficiency.

Abstract: The present application relates to the technical field of architectural engineering. Disclosed are a slab joint leakage-proof structure of a prefabricated roof panel, a prefabricated roof panel and a prefabricated roof panel system. The slab joint leakage-proof structure comprises a first leakage-proof layer. The first leakage-proof layer comprises two flexible structures which abut against each other and are arranged at the joint of a main rib on the long side of the roof panel and a main rib on the long side of an adjacent roof panel. Either of the flexible structures comprises a main body portion sealably attached to the main rib, and at least one protruding portion which is fixedly disposed on the main body portion, protrudes and extends into the joint, and can tightly abut against the other flexible structure. The protruding portions of the two flexible structures can enclose an air cavity layer sealably isolated from the outside.

Abstract: A robotic welding device employing a flexible guide rail comprises: a control box (2) pre-storing various welding processes and generating a welding parameter; a wire feed mechanism (7) feeding a welding wire to a welding gun (4); a flexible guide rail (8) attached to a welding component with the flexibility thereof; a welding robot comprising a robot body (3) and a welding gun (4), the robot body (3) being movably disposed on the flexible guide rail (8) along the same, and the welding gun (4) being disposed on the robot body (3) and controlled by the same to weld the welding component; a demonstrator (6) signally connected with the welding robot and the control box (2), controlling, a traveling path and an operation position of the welding robot, and adjusting oscillation and welding operations of the welding gun (4) according to an instruction of the control box (2); a remote control terminal (11) signally connected with the control box (2) so as to remotely monitor and configure the welding parameter, and