Large-span self-anchored steel box girder suspension bridge track lofting and measuring method

Abstract

The invention discloses a large-span self-anchored steel box girder suspension bridge track lofting and measuring method. The method comprises the steps: controlling elevation with a tower column as the benchmark; conducting lofting along a girder surface to control a base mark, and conducting lofting along the center line of a track line to densify the base mark; obtaining the influence of the girder surface temperature on the elevation, determining a concrete pouring time period according to the influence, and formulating an elevation temperature fitting line; formulating an elevation load fitting line according to the load of later construction; correcting the actually measured surface line shape of the large bridge by using the elevation temperature fitting line, the elevation load fitting line and the track structure design height to obtain a track laying fitting line shape; calculating the structural thickness of the ballast bed according to the height difference between the railsurface and the girder surface, and then laying the ballast bed; erecting track panels section by section, and then laying a track. By arranging the encryption base mark, elevation measurement is facilitated, the stable line type of the bridge is conveniently determined, and measurement control in construction is facilitated; in the track arranging process, a relative elevation difference value fixed control method is used for correction again, and the problem that bridge deck track laying is affected due to the fact that the bridge deck elevation is dynamically changed all the time is effectively solved.

Description

technical field [0001] The invention relates to a track setting out and measuring method, in particular to a track setting out and measuring method of a large-span self-anchored steel box girder suspension bridge, belonging to the technical field of steel box girder suspension bridge measurement construction. Background technique [0002] At present, most of the railway bridges at home and abroad use concrete structures and a few steel structures. The railway suspension steel structure bridge was first applied in the Jinsha River Bridge in 2017, but the bridge adopts a ballasted track structure, and mainly uses steel box girders combined with concrete girders. The ballastless track suspension bridge with load-bearing structure is firstly applied in the Chongqing track loop crossing the Yangtze River of the present invention. [0003] The construction of the long-span river-crossing subway bridge is difficult and has a high risk factor. In addition, due to the unbroken shipp...

AI Technical Summary

Problems solved by technology

[0003] The construction of the subway long-span river-crossing bridge is difficult and the risk factor is high

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