Method for building prestressed concrete through bowstring arch bridge

Abstract

The invention provides a method for building a prestressed concrete through bowstring arch bridge, which solves the problem that convertible construction needs to be performed according to a beam in advance of arched roof tunneling system because of the traffic limitation of equipment, and comprises the following steps: building a stable midspan temporary buttress, and casting the box girder of the main girder of the arch bridge and a concrete arch springing which is 0.4 meter high by using a conventional method; after the concrete strength and the elastic modulus of the box girder of the main girder of the arch bridge reach above 90 percent of design values and are not less than 10 days, tensioning a longitudinal prestressed steel bundle and a horizontal prestressed steel bundle according to the design demand; when a bridge girder erection machine passes the main girder of the arch bridge, ensuring the crack-resistant safety factors of the top plate and the bottom plate of the main girder of the arch bridge to be greater than 1.1, and the safety factor of the section strength at the position of the maximum bending moment of the main girder of the arch bridge to be greater than 2.2; and from the second suspenders at both ends to the midspan direction, tensioning the suspenders in sequence, finally, tensioning the first suspenders at both ends, then, removing the midspan temporary buttress, and performing bridge deck construction. According to the method for building the prestressed concrete through bowstring arch bridge, the conversion which is simple and easy to implement between the temporary buttress and the stress structure system of an arch ring is realized.

Description

technical field [0001] The invention relates to a construction method of a tied-rod arch bridge, in particular to a construction method of a prestressed concrete under-supporting type tied-rod arch bridge which needs to undergo stress structure system conversion due to the influence of a transport frame. Background technique [0002] Tied arch bridge is a special form of arch bridge. In the arch span structure, the two basic structures of beam and arch are combined to bear the load together, and give full play to the structural characteristics and combined effects of beam bending and arch compression. , to save material. Tied arch bridge is a combined structure bridge composed of arch ribs, suspenders (columns), tie rods, carriageway girders (slabs) and bridge deck systems, etc. From its force characteristics, the tied arch bridge is an organic combination of arch bridge, girder bridge and suspension bridge. The tied arch bridge is an externally statically indeterminate s...

AI Technical Summary

Problems solved by technology

[0003] The invention provides a method for constructing a prestressed concrete under-supported tied-bar arch bridge, which solves the technical problem of switching construction according to the beam-first-arch system due to the transportation restrictions of the frame-transporting equipment

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