UHPC-NC mixed box girder, large-span rigid frame bridge and construction method of large-span rigid frame bridge

Abstract

The invention discloses a UHPC-NC mixed box girder for a large-span rigid frame bridge. The UHPC-NC mixed box girder comprises a UHPC ribbed bottom plate, an NC web plate and an NC top plate, and theUHPC ribbed bottom plate is fixedly connected with the NC top plate into a whole through the NC web plate. The invention further provides a large-span rigid frame bridge which comprises pier top beamsections, first beam sections and second beam sections, the first beam sections are located on the two sides of the pier top beam sections and are symmetrically arranged along the pier top beam sections, and the second beam sections are located on the outer sides of the first beam sections and are symmetrically arranged along the pier top beam sections. The invention further provides a construction method of the large-span rigid frame bridge. According to the large-span rigid frame bridge, the bottom plate of the high-pressure stress area is the UHPC ribbed plate, creep of the UHPC prefabricated plate after high-temperature steam curing is extremely small, the UHPC prefabricated plate hardly shrinks and has ultrahigh compressive strength, the compressive strength of the bottom plate is improved, the creep effect is remarkably reduced, and the risk of later downwarping and cracking of the large-span continuous rigid frame bridge is greatly reduced.

Description

technical field [0001] The invention belongs to the field of bridges, in particular to a box girder, a rigid frame bridge and a construction method thereof. Background technique [0002] Long-span prestressed concrete (PC) rigid frame bridge is a commonly used bridge type with strong spanning capacity, good structural integrity, simple construction, good economy, and smooth driving. It has become the main force in the world with a span range of 100-250m Bridge type. [0003] However, during the construction and later operation of long-span PC rigid-frame bridges, there are common diseases such as serious box girder concrete cracking and excessive mid-span deflection of the main span. These diseases affect the applicability, safety and durability of bridge structures. If it is not effectively guaranteed, it may affect the normal function of the bridge in serious cases, and it has not been effectively solved so far. Cracking and deflection problems of long-span PC rigid fram...

AI Technical Summary

Problems solved by technology

However, concrete creep is an inherent characteristic of concrete and is unavoidable. The long-span PC rigid frame bridge made of concrete inevitably has problems of cracking and deflection.

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