Method for hard overhead construction of frame culvert of existing railway

Abstract

The invention discloses a method for hard overhead construction of a frame culvert of an existing railway. The method comprises the steps that firstly, symmetrically arranging two fulcrum hole diggingpiles on the two sides of each line; when the train travels slowly, horizontally arranging transverse lifting beams arranged below the line rails at intervals in a penetrating mode; transporting thelongitudinal beams to a construction site, placing the longitudinal beams in place and connecting the longitudinal beams with the transverse lifting beams under the condition of power failure of the contact net, slowing down the train, excavating a pilot tunnel at the position of a foundation pit to be excavated, and detecting the trend and position of an existing pipeline; conducting downward excavation at the position of a foundation pit to be excavated in a layered mode, wherein the excavation depth is 1.5-2 m each time, then arranging anchor rods on the side slope in a hit mode, hanging reinforcing meshes on the anchor rods, spraying concrete to form a stable protective layer till the design depth is met; sequentially constructing a foundation, a bottom plate, a side wall and a top plate of the frame culvert; and backfilling the transition section, dismounting the longitudinal beams , sequentially pulling the transverse lifting beams out from the slow moving points to complete construction. An excavation method of relay layered excavation and layered protection is adopted, stability of a foundation pit slope is guaranteed, and driving safety of an existing line is guaranteed.

Description

technical field [0001] The invention relates to a cut-and-cast-in-place construction method for an existing railway frame bridge, in particular to a method for constructing a frame culvert with hard overhead construction on the existing railway. Background technique [0002] With the development of my country's railways, existing stations need to be continuously remodeled. In order to meet the needs of station wiring or drainage, deep foundation pits need to be excavated under the existing railway, and frame culverts should be cast in place. figure 1 Shown is the plan view of the frame culvert under the original five existing railway lines. It can be seen from the figure that the frame culvert to be constructed needs to pass under the existing basic platform, the second platform and the third platform, and the construction frame Before the culvert, it is necessary to excavate the deep foundation pit for the overhead line, and the frame culvert can be poured on site after th...

AI Technical Summary

Problems solved by technology

Since the railway department requires that the speed limit of the vehicle should not be lower than 45km / h on the basis of ensuring the safety of the vehicle during the reconstruction of the station, so when encountering the first and second types of soil, the excavation of the deep foundation pit must be supported by the side slope, but according to Traditional construction experience has not formed a systematic treatment method for the excavation of deep foundation pit slope protection for the construction of cast-in-place frame culverts in existing stations

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