Web-bar-free prestress self-maintaining combination beam based on permanent post-tensioning prestress UHPC sleeving formwork and construction method

Abstract

The invention discloses a web-bar-free prestress self-maintaining combination beam based on a permanent post-tensioning prestress UHPC sleeving formwork and a construction method. The combination beamcomprises a top plate, the sleeving formwork and self-maintaining concrete. The sleeving formwork comprises a base plate, a web formwork and an end head inserting plate. The base plate, the web formwork and the end head inserting plate are formed by prefabricating ultra-high-performance concrete. An inserting groove shaped like a hollow square encircled by another hollow square is prefabricated in the upper surface of the base plate. According to the combination beam, the UHPC serves as permanent formwork materials, the self-maintaining concrete fills an inner cavity of a web body, traditional hoops are removed, the material characteristics of the UHPC and the concrete are brought into full play, the beam structure form is optimized, the link of concrete manual maintaining is omitted, andmeanwhile, the problem that a pure-prestress UHPC beam is high in manufacturing cost is solved. The combination beam is applicable to assembly type construction and can be applicable to structures such as I-shaped beams and box girders. According to the construction method, the construction technology is simple, the construction efficiency is high, and the problem that the construction period ofa traditional prestress concrete beam is long can be solved.

Description

technical field [0001] The invention relates to the field of civil engineering, in particular to a prestressed self-maintaining composite beam without web reinforcement based on a permanent post-tensioned prestressed UHPC suit formwork and a construction method. Background technique [0002] Prestressed concrete beams are usually prefabricated with formwork during construction, the binding of steel bars is complicated, the construction process is cumbersome, and the quality of concrete pouring is not easy to control. The survey of existing prestressed concrete bridge diseases found that the prestressed concrete beams in service have serious diseases, such as structural cracking and steel corrosion, which not only affect the safety of the bridge, but also affect the safety and performance of the structure. Ultra-high performance concrete (UHPC) is a cement-based material with excellent physical and mechanical properties. It has high tensile and compressive strength, good toug...

AI Technical Summary

Problems solved by technology

The present invention is suitable for prefabricated construction, and can be applied to structural forms such as I-shaped beams and box girders. The construction method in the present invention has simple construction technology, high construction efficiency, and can solve the problem of long construction period of traditional prestressed concrete beams.

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