Large cantilever steel box girder on the same floor for highway and railway

Abstract

The invention discloses a large-cantilever steel box beam with a highway and a railway on the same layer. The large-cantilever steel box beam comprises a box beam top board and cantilever top boards, wherein the cantilever top boards are located on the longitudinal outer sides of the box beam top board, the highway is arranged on the cantilever top boards, the railway is arranged on the box beam top board, the two longitudinal sides of the lower end face of the box beam top board are supported by load bearing structures, a box beam bottom board is arranged between the bottoms of the load bearing structures, and a box type structure is defined by the box beam top board, the load bearing structures and the box beam bottom board. According to the large-cantilever steel box beam with the highway and the railway on the same layer, the highway and the railway are arranged on the same layer, so that compared with a steel box beam with a traditional layered arrangement mode, the large-cantilever steel box beam has the advantages that the line elevation is small, the length of an approach bridge is small, the occupied range of the grade separation is small, project investment can be saved, the vision is wide, the landscape is good, and the novel large-span highway and railway combined construction bridge arrangement mode is achieved.

Description

technical field [0001] The invention relates to the technical field of bridge construction, in particular to a large cantilever steel box girder on the same floor for highways and railways. Background technique [0002] At present, domestic long-span bridges for road and railway use layered steel truss girders. Although the technology of steel truss girders is mature, there are still the following imperfections: [0003] First of all, the layered layout of the road and railway has increased the elevation of the highway bridge deck, increased the length of the approach bridge, and correspondingly increased the construction cost; [0004] Secondly, due to factors such as joint structure, many spliced ​​plates, and large slenderness ratio of weakened bolt holes, the material utilization rate of steel truss girders is not high, and the form of hybrid beams cannot be used, and the steel consumption is large; [0005] Thirdly, the steel truss girder has a large overall cross-sect...

AI Technical Summary

Problems solved by technology

[0003] First of all, the layered layout of the road and railway has increased the elevation of the highway bridge deck, increased the length of the approach bridge, and correspondingly increased the construction cost;

[0004] Secondly, due to factors such as joint structure, many spliced ​​plates, and large slenderness ratio of weakened bolt holes, the material utilization rate of steel truss girders is not high, and the form of hybrid beams cannot be used, and the steel consumption is large;

[0005] Thirdly, the steel truss girder has a large overall cross-section height, many rods, a large wind resistance coefficient, and the blunt body cross-section has poor wind resistance.

[0006] Finally, there are many steel truss girder members. Although the transportation and hoisting are convenient, the splicing construction of the entire segment is difficult, while the splicing construction progress of a single member is slow and requires high construction accuracy.

[0007] The traditional road steel box girder has high torsional rigidity and good wind resistance, and the on-site hoisting accuracy requirements are slightly lower, and the mixed beam form can be used, but the bridge deck is widened after the railway is added in the middle of the section, so that the lateral force on the bridge deck increases sharply , while the longitudinal stress margin is large, the material utilization rate is not high, and the economy is poor

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