Partial steel web single-box four-chamber composite box girder suitable for low-tower cable-stayed bridges

Abstract

Provided is a steel web single-box four-chamber combined box girder applied to extradosed cable-stayed bridge equal-height segments. The box girder comprises a prestressed concrete top plate, a prestressed concrete bottom plate, two prestressed concrete inclined webs and three intermediate webs. The prestressed concrete top plate is horizontally arranged on the upper portion, and the prestressed concrete bottom plate is horizontally arranged on the lower portion. The two prestressed concrete inclined webs are connected between two ends of the prestressed concrete top plate and two ends of the prestressed concrete bottom plate respectively. The intermediate webs are in a steel structure, and the three intermediate webs are perpendicularly connected between the middle portions of the prestressed concrete top plate and the prestressed concrete bottom plate at intervals. According to the box girder, steel plates are used as the intermediate webs, due to the fact that steel products have strong compression-resisting strength and bend-resisting strength, the thicknesses of the top plate, the bottom plate and the inclined webs can be reduced properly, and the distance between the inclined webs and the intermediate webs can be reduced properly. A self-weight load effect is effectively weakened, and moreover the weights of the steel webs are far lower than the weight of reinforced concrete in the same size, so that self-weight of the box girder and the self-weight of an entire cable-stayed bridge can be reduced, and the span of the bridge is increased.

Description

Technical field [0001] The invention belongs to the technical field of bridge structure design and construction, and particularly relates to a partial steel web single-box four-chamber combined box girder suitable for low-tower cable-stayed bridges with equal height. Background technique [0002] The low-tower cable-stayed bridge is a new bridge type that has appeared in the past 20 years. It has the advantages of superior structural performance and good economic indicators, so it has been widely used. figure 1 It is a schematic diagram of a commonly used low-tower cable-stayed bridge structure. Such as figure 1 As shown, this kind of low-tower cable-stayed bridge mainly includes the pylon 1, the pier 2, the beam 3 and the cable-stayed cables not shown in the figure; among them, the beam 3 changes from the non-cable area near the tower end to the high section 4 and the cable area The equal-height section 5 and the folded section 6 connected between the variable-height section 4 a...

AI Technical Summary

Problems solved by technology

But there is following problem in this low-tower cable-stayed bridge of prior art: as mentioned above, because the box girder of single box four chambers is reinforced concrete structure, so self weight is relatively big, makes the spanning capacity of bridge relatively small, and Cracks are prone to occur on the web, which adversely affects the overall structure, resulting in poor durability. In addition, since prestressed steel bars need to be installed in the web of this single-box four-chamber box girder, the construction is relatively complicated and the processing time is long , and inconvenient to transport

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