Prefabricated ultra-high-performance concrete pi-shaped beam unit, bridge structure and construction method thereof

Abstract

The invention discloses a prefabricated ultra-high-performance concrete pi-shaped beam unit applicable to bridge construction. The prefabricated ultra-high-performance concrete pi-shaped beam unit is formed by integrally prefabricating a T-shaped double-main beam and bridge deck slabs, wherein the T-shaped double-main beam comprises two main beam webs which are arranged in parallel; a gridded thin slab piece is adopted as each bridge deck slab, and longitudinal ribs and transverse ribs are arranged at the lower part of each gridded thin slab piece; one or two sides of each bridge deck slab is / are set as a connection part(s); a connecting steel bar which is connected with another adjacent pi-shaped beam unit extends out of each connecting part. The pi-shaped beam unit is spliced along the transverse direction of a bridge, a cast-in-situ seam is formed in a butt joint, the connecting steel bar is bound at the cast-in-situ seam, and a longitudinal steel bar is configured at the cast-in-situ seam. A construction method of a pi-shaped bridge structure comprises the following steps of firstly, prefabricating the ultra-high-performance concrete pi-shaped beam unit; secondly, transversely splicing the unit on a construction site; thirdly, binding the connecting steel bar at a longitudinal seam, and casting ultra-high-performance concrete in situ; finally, performing maintenance to complete construction. The prefabricated ultra-high-performance concrete pi-shaped beam unit has the advantages of being light in dead weight, high in durability, capable of effectively reducing the cracking risk of a beam body and the like.

Description

technical field [0001] The invention relates to a bridge component, a bridge body structure and construction thereof, in particular to a prefabricated ultra-high performance concrete beam unit, a bridge structure and a construction method thereof. Background technique [0002] Prefabricated prestressed concrete beams have the advantages of simple structure, clear stress, low cost, and convenient erection, and have been widely used in bridge structures. However, due to the low tensile strength and large shrinkage and creep of ordinary concrete materials, under the long-term action of vehicle loads, the beam body is prone to cracks, and the reinforced concrete or asphalt concrete bridge deck and waterproof layer at the wet joints are prone to cracking and damage, and the bridge deck seeps The main beam is eroded, and the durability is greatly reduced. In addition, in commonly used prefabricated components such as box girders, T beams, I-beams, and hollow slabs, the main girde...

AI Technical Summary

Problems solved by technology

However, due to the low tensile strength and large shrinkage and creep of ordinary concrete materials, under the long-term action of vehicle loads, the beam body is prone to cracks, and the reinforced concrete or asphalt concrete bridge deck and waterproof layer at the wet joints are prone to cracking and damage, and the bridge deck seeps Erosion of the main beam, the durability is greatly reduced

In addition, in commonly used prefabricated components such as box girders, T beams, I-beams, and hollow slabs, the main girder will produce inverse camber after tensioning the prestressed steel strands. When the inverse camber value deviates, it will often affect the Accurate positioning and accurate erection of the beams make it difficult to connect the beams horizontally, and even cause partial staggered platforms in serious cases, affecting the function and appearance of the bridge

[0003] In the existing technology, in order to save materials, the beam body often adopts the form of variable cross-section, and the weight is reduced by reducing the thickness of the web of the main beam. At the same time, in order to improve the transverse stiffness of the bridge, the precast concrete beam sections are arranged at a certain distance between the end and the middle. There are multiple diaphragms, which makes it more difficult to make steel bars, and the formwork system is more complicated, making it difficult to guarantee the quality of concrete pouring

As for the cracks, it is generally improved by improving the construction quality and optimizing the structural design. However, due to the limitation of the material properties of ordinary concrete, the cracking problem has not been fundamentally solved.

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