Prestressed ultrahigh-performance concrete continuous box girder bridge and construction method thereof

Abstract

The invention discloses a prestressed ultrahigh-performance concrete continuous box girder bridge which comprises piers and an ultra-high performance concrete box girder. The box girder has a wholly or partially external prestressed system in the longitudinal direction of the box girder bridge and mainly comprises a top plate, a bottom plate, a web plate and a diaphragm plate, wherein at least one of the top plate, the bottom plate, the web plate and the diaphragm plate is a sheet. The construction method of the prestressed ultrahigh-performance concrete continuous box girder bridge is a segmental prefabricating and suspended-splicing method and mainly comprises the following steps: constructing pile foundations and the piers, mounting blocks No.0 on the piers, splicing all sections of the box girder symmetrically on two sides of the blocks No.0 in a suspending way, erecting side spans by using a support erecting method, carrying out side span closure, carrying out midspan closure, and stretching prestressed steel strands in all construction stages to finish construction. The prestressed ultra-high performance concrete continuous box girder bridge has the advantages of simple structure and light dead weight, the crack risk of the box girder is reduced, and the method is suitable for constructing a long-span bridge.

Description

technical field [0001] The invention relates to a continuous box girder bridge and a construction method thereof, in particular to a continuous box girder bridge using special building materials and a construction method thereof. Background technique [0002] Due to the advantages of mature technology and good economy, prestressed concrete girder bridge has gradually become the mainstream bridge type within the span range of 20m to 300m. However, when the span of the prestressed concrete girder bridge reaches 400m or more, its economic efficiency becomes poor due to its structural weight and the low tensile strength of traditional concrete; at the same time, the prestressed concrete box girder bridge still has major problems. Excessive mid-span deflection of beams and cracking of box girders. In addition, the building height of 400m or larger span arch bridges is too high, or its key stress-bearing components (suspension rods or tie rods) are exposed to the atmosphere all t...

AI Technical Summary

Problems solved by technology

However, when the span of the prestressed concrete girder bridge reaches 400m or more, its economic efficiency becomes poor due to its structural weight and the low tensile strength of traditional concrete; at the same time, the prestressed concrete box girder bridge still has major problems. Excessive mid-span deflection and cracking of box girder

In addition, the building height of 400m or larger span arch bridges is too high, or its key stress-bearing components (suspension rods or tie rods) are exposed to the atmosphere all the year round and are prone to corrosion, which greatly reduces the durability of this type of bridge structure

The construction cost of 400m-span steel structure girder bridge and 400m-span cable load-bearing system bridge is relatively high

At present, long-span box girder bridges also use high-performance lightweight aggregate concrete in the middle of the main span (such as Stolma Bridge in Norway with a main span of 301m) and steel box girders in the middle of the main span (such as the Chongqing Bridge with a main span of 330m). Shibanpo Yangtze River Bridge double-track bridge) and other methods to improve its spanning capacity, and methods such as setting web vertical prestressed reinforcement to reduce the risk of box girder cracking, although these methods have certain effects, but the design and construction process of these schemes are more complicated At the same time, problems such as box girder cracking have not been fundamentally resolved

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