Method of Constructing Steel-Concrete Composite Beams Using Mixed Cables

Abstract

The invention discloses a method for constructing a reinforced concrete combined beam through hybrid inhaul cables. The method includes the steps that firstly, steel beam units are prefabricated, eachsteel beam upper flange is provided with the even number of temporary lifting sheets, meanwhile, inhaul cable devices are correspondingly arranged on a bridge girder erection machine, construction isconducted so that a first steel beam can be erected in position, suspension clasps at the bottoms of the inhaul cables on the bridge girder erection machine are connected with the lifting sheets of the corresponding steel beam upper flange, a mid-span region is in a vertical state, and the end portions are in a cable-stayed state; the inhaul cables are tensioned till the cable force reaches a setvalue, and then the inhaul cables are locked; precast concrete bridge deck slabs are installed; bridge deck slab wet joint concrete is poured; after the bridge deck slab wet joint concrete reaches the designed strength, the inhaul cables and the lifting sheets are disconnected; then a second steel beam is erected, and construction of the two steel beams is finished; and similarly, construction ofa whole bridge is finished. By the adoption of the method, the material use efficiency of a traditional non-support construction reinforced concrete combined beam can be improved, meanwhile, the concrete anti-cracking performance of a hogging moment region of the combined beam can be improved, a series of beneficial effects such as convenient and quick construction are achieved, and the method has wide application prospects in large-middle-span combined beam erection.

Description

technical field [0001] The invention relates to a construction method of a steel-concrete composite beam, in particular to a method for constructing a steel-concrete composite beam by using mixed cables. Background technique [0002] The steel-concrete composite beam has a series of advantages such as light structure, large spanning capacity, and fast construction speed. It can meet the construction requirements of urban viaducts and long bridges across rivers and seas to the greatest extent, and has been more and more widely used in modern bridge structures. [0003] Due to the different construction procedures and construction methods of steel-concrete composite beams, their stress states are also different. According to the stress state of the composite beam construction, it can be divided into two types of structures: 1) Live-loaded composite beams, that is, construction without supports. During the construction process, the steel beams and concrete are all borne by the ...

AI Technical Summary

Problems solved by technology

However, if limited by construction conditions, when it is impossible or unsuitable to erect supports at the bridge site, construction methods without supports are often used for construction. During the construction of traditional steel-concrete composite beams without supports, the steel beams need to bear their own weight and construction loads. and concrete self-weight, etc., in order to meet the construction requirements, the rigidity of the steel beam is required to be greater than that of the dead-load composite beam, which causes a waste of materials to a certain extent for the steel-concrete composite beam that bears the same load after the bridge is completed

[0005] On the other hand, for steel-concrete composite simply supported beams, the upper edge of the concrete bridge deck is under compression, and the lower edge of the steel girder is under tension. Insufficient, but at the same time, the concrete roof in the negative moment area of ​​the pier top of the combined continuous girder bridge is inevitably in a state of tension, which can easily cause concrete cracking, thus affecting the working performance and service life of the combined continuous girder bridge

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