Precast ultra high performance concrete-ordinary concrete composite beam bridge structure and construction method

Abstract

The invention relates to A precast ultra high performance concrete-ordinary concrete composite beam bridge structure and a construction method thereof, wherein the bridge structure comprises a beam element and a bridge deck, wherein the beam element is integrally precast with ultra-high performance concrete material, and the bridge deck is cast-in-situ with common concrete over the beam element; The bottom of the beam element is provided with channel steel. The invention also comprises a precast ultra-high performance concrete. Construction method of ordinary concrete composite beam bridge structure. On the one hand, the invention not only improves the overall strength of the bridge, but also saves the working procedure of dismantling the bottom formwork in the construction process, so that the prefabrication of the structure is easier; On the other hand, the lightness of the main girder can be realized, which not only reduces the requirement of the bridge substructure and improves thespan capacity of the bridge, but also makes the structure assembling and transportation easier.

Description

technical field [0001] The invention relates to bridge components, bridge structures and construction thereof, in particular to a prefabricated ultra-high performance concrete-ordinary concrete composite beam bridge structure and a construction method. Background technique [0002] Prefabricated prestressed concrete beams have the advantages of simple structure, clear stress, low cost, environmental protection, and convenient erection, and have been widely used in bridge structures. Ordinary concrete has low tensile strength and large shrinkage and creep. Under the long-term action of vehicle load and other factors, cracks in the beam body will develop, and reinforced concrete at wet joints will crack, and its durability will be greatly reduced. UHPC (Ultra High Performance Concrete) has the advantages of high elastic modulus, high compressive and tensile strength, and good creep characteristics, which can reduce the size of the structure, reduce the weight of the structure,...

AI Technical Summary

Problems solved by technology

[0003] In bridges with a span of 20m to 60m, the main cross-sectional forms are T-shaped, independent I-shaped and box-shaped. Among them, prefabricated T-shaped and independent I-shaped beams are prone to overturning during erection, and these bridges have a large number of prefabricated units. It is difficult to control the assembly accuracy during the construction process; the number of prefabricated box girders and prefabricated section box girder components is too large, the amount of formwork and steel bar binding is large, the construction process is complicated, the weight of the overall box girder is heavy, and transportation and hoisting are difficult

[0004] In the prior art, UHPC duplex girder structure is also used, but it needs to use longitudinal stress reinforcement, which has the following defects: (1) When a large diameter longitudinal stress reinforcement needs to be installed, the UHPC pouring of the lower beam flange will not be dense; When a large number of large-diameter longitudinally loaded steel bars need to be installed in the horizontal direction, due to the width limitation of the lower flange of the beam, the horizontal spacing of the steel bars is relatively dense, which will lead to the inconsistency of UHPC pouring between the longitudinally loaded steel bars; When multi-layer welding (such as stacking bars), the efficiency of longitudinal reinforced steel bars is low; (2) the use of longitudinal steel bars will increase the cross-sectional area of ​​the beam (because the thickness of the protective layer must be considered); (3) it is necessary to set a bottom form, and the bottom form Formwork removal is time-consuming, and the efficiency of bridge construction is low; (4) The amount of steel bar binding is large

Images