Secondary tensioning prestressed assembly-type corrugated steel web composite beam and construction method thereof

Abstract

The invention discloses a secondary tensioning prestressed assembly-type corrugated steel web composite beam. The composite beam comprises a composite beam unit which is formed in a way that a plurality of prefabricated corrugated steel web beam bodies are connected, each prefabricated corrugated steel web beam body comprises a corrugated steel web, a concrete top plate and a concrete base plate, the concrete top plate is connected with the corrugated steel web through an upper connecting piece, and the concrete base plate is connected with the corrugated steel web through a lower connecting piece; the transverse connecting end of each of the concrete top plate and the concrete base plate is provided with a transverse connecting steel bar, vertical connecting steel bars are arranged in the concrete top plate and the concrete base plate in balance, primary tensioning prestressed channels and secondary tensioning prestressed channels are arranged in the concrete base plate symmetrically, primary tensioning prestressed steel beams are arranged in the primary tensioning prestressed channels in a penetrating manner, and secondary tensioning prestressed steel beams are arranged in the secondary tensioning prestressed channels in a penetrating manner. The invention also provides a construction method of the composite beam. According to the invention, the prestressed steel beams are tensioned twice, inflected arch phenomena, of the prefabricated corrugated steel web beam bodies, caused by concrete shrinkage and creep can be reduced, the erection precision of the bridge is improved, and the usage performance of the prestressed assembly-type corrugated steel web composite beam can be improved.

Description

technical field [0001] The invention relates to an assembled corrugated steel web composite beam, in particular to a secondary tension prestressed assembled corrugated steel web composite beam, and also relates to a construction method of the composite beam. Background technique [0002] Concrete bridges have always been the most widely used in our country, but concrete bridges use a lot of sand and gravel, have little reusable value after dismantling, and cause great environmental pollution, while steel-concrete composite structure bridges minimize the cost of construction without increasing the cost. The amount of concrete used and the steel structure can be recycled. It is the best alternative bridge type for concrete bridges. In recent years, with the continuous innovation and practice of corrugated steel webs in bridge engineering, fabricated corrugated steel web composite beams have gradually become an important structural form of steel-concrete composite bridges and h...

AI Technical Summary

Problems solved by technology

[0003] 1. During factory prefabrication, the prestressed steel tendons in the corrugated steel web prefabricated girder unit body have been stretched at one time. Under the influence of shrinkage and creep, the prefabricated girder body will have a large anti-arch, which affects the construction control accuracy during erection and the completion of the bridge. The working performance of the rear structure;

[0004] 2. The wet joints are poured after the erection of the prefabricated beam body. Since the wet joints need to be prestressed in the form of external steel beams, the structure needs to be equipped with external beam diverters and steel beam shock absorbers and other auxiliary facilities, which increases the The construction process affects the construction period;

[0005] 3. The external prestressed steel beam needs to use epoxy coating as a protective layer, and its unit price is higher than that of the internal prestressed beam, which increases the construction cost of this type of bridge;

[0006] 4. Due to the long-term exposure of the external steel beam to the atmosphere, its own coating will gradually deteriorate, and water, dust, etc. will corrode it, and the external steel beam is difficult to replace, which will affect the durability of the bridge structure;

[0007] 5. If the post-cast wet joint adopts reinforced concrete structure, there will be a large stress difference between the prefabricated part and the post-cast part, and the force under the action of factors such as shrinkage and creep is not clear

[0008] In view of the above shortcomings, the existing assembled corrugated steel web composite beams have certain limitations in the actual application process

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