Large-span steel cross-beam hoisting construction method for crossing existing line portal pier

Abstract

The invention discloses a large-span steel cross-beam hoisting construction method for crossing an existing line portal pier. The method comprises the following steps: step S1: according to a set position, installing a temporary support on a temporary padstone installed on the portal pier; step S2: according to a design position, accurately setting out a cross-shaped axis of a steel cross beam onthe pier top of the portal pier, and correspondingly setting out a cross-shaped axis on the steel cross beam, which is used for the installing and positioning of the steel cross beam; step S3: hoisting the steel cross beam by using a hoisting machine, in a positioning process, adjusting the position of the exterior of the steel cross beam by using a crowbar, and adjusting the position of the interior of the steel cross beam by using a chain block, until the cross-shaped axis on the steel cross beam is completely aligned with the cross-shaped axis on the pier top, and completing the beam fall;and step S4: welding a bottom plate of the steel cross beam and the temporary support. Through the alignment of cross curves, the construction precision is guaranteed, each item of the measured data of the hoisted steel cross beam is effectively controlled to be within a deviation area of the design requirements, a good effect is achieved, the hoisting time is shortened at the same time, and construction speed is rapid.

Description

technical field [0001] The invention relates to the technical field of railway engineering, in particular to a construction method for hoisting a large-span steel beam spanning an existing line portal pier. Background technique [0002] When high-speed railways and intercity railways cross the existing lines, in order to ensure the normal passage and safety of the existing lines, it is a more convenient method to adopt the existing lines of the gate-type pier structure. The shape of the gate-type pier is simple and light, and the stability is good , but it is often used to cross busy existing lines with high safety risks, long construction time for key points, and narrow construction sites. [0003] The beam of the portal pier adopts a steel structure, and the top of the pier is equipped with a temporary pad stone, and a temporary support is installed on the temporary pad stone. The temporary support includes the upper plate of the support, the arc plate of the support, the ...

AI Technical Summary

Problems solved by technology

When hoisting, the fixed end adopts the steel pin that welds the upper plate of the temporary support and the arc plate of the support to the bottom plate of the beam, and the steel pins are aligned and connected during hoisting. The PTFE plate is bonded above the arc plate of the support. When hoisting, the upper plate of the support directly aligns the arc plate of the support. Due to measurement errors, deformation and temperature changes of the steel beam after hoisting, the alignment is difficult, and only Enlarging the reserved hole connecting the bottom plate of the support with the steel pin and changing the position of the steel pin will inevitably affect the erection accuracy of the steel beam, and the construction time will be long. Complete the hoisting within the specified time, there is a risk of delay

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