A construction method for jacking up a long-span concrete-filled steel tube tied arch bridge

Abstract

The invention discloses a construction method for jacking up a long-span concrete-filled steel pipe tied arch bridge. The bridge to be jacked up includes a main bridge and two approach bridges. When jacking up the bridge to be jacked up, steps are included: 1. Preparation before jacking up Work: Separate the connection ends of all longitudinal girders in the two approach bridges from the assembled girder body, and separate the assembled girder body from the two supporting piers, and simultaneously separate all the longitudinal girders in each approach bridge from the supported The lower support structure of the approach bridge is separated; 2. Jacking: When jacking up the bridge to be lifted, the main bridge and the two approach bridges are jacked up separately; 3. The lower structure of the main bridge is raised. The method of the present invention is reasonable in design, easy in construction and good in use effect. The main bridge and the two approach bridges are respectively jacked up, and the structures and layout positions of the adopted approach bridge jacking system and the main bridge jacking system are specifically limited. The jacking construction process of the long-span arch bridge is completed simply and quickly, and the jacking process is safe and reliable.

Description

technical field [0001] The invention belongs to the technical field of bridge jacking construction, and in particular relates to a jacking construction method of a large-span concrete-filled steel tube tie-bar arch bridge. Background technique [0002] Bridge jacking construction (also known as bridge jacking technology) refers to the adoption of an overall hydraulic synchronous lifting scheme, that is, using the original cast-in-place piles to bear the load without destroying the original bridge deck pavement, railings, sidewalks, and beams and slabs. Connections, etc., first use the hydraulic jacking device to withstand the overall structure of the bridge, then cut off the columns under each pier and platform cap beam, and then operate the hydraulic jacking device to raise the bridge as a whole to the design height, and finally connect the long column steel bars Formwork pouring of the second stage concrete. The bridge superstructure refers to the general term for the par...

AI Technical Summary

Problems solved by technology

Among them, when jacking up the main bridge, there are the following construction problems: First, the project is located on the expressway, and the jacking construction must interrupt the traffic, and change the two-way traffic of the double-width bridge to the two-way traffic of the single-width bridge, which will affect the traffic of the expressway Larger, short road closure time, tight construction period, and the necessary closure time during construction is short, so a construction plan that has little impact on navigation must be adopted; second, the jacking weight of the main bridge is huge, and the single jacking weight is 7,000 tons ;Third, during the jacking process, the upper structure of the bridge is in a suspended state, and there are great potential safety hazards, and effective measures must be taken to resolve the above risks to ensure the safety of the bridge and construction personnel; Fourth, the jacking height is relatively high, and the jacking With a height of 2.16m, there are many temporary pads and jacking cycles, which put forward higher requirements for the overall stability of the supporting structure. It is necessary to ensure that the vertical and horizontal support system is firm, reliable and stable.

Correspondingly, when jacking up the approach bridge, there are the following construction problems: first, the number of spans of the approach bridge is large and the jacking weight is heavy, the risk points are scattered, and the overall jacking construction process is difficult to control; second, during the jacking process, the upper part of the bridge The structure is in a suspended state, and there are great potential safety hazards. Effective measures must be taken to resolve the above risks to ensure the safety of the bridge and construction personnel; third, the jacking height is relatively high, with a jacking height of 2.16m. Temporary pads and jacking There are many cycles, which put forward higher requirements for the overall stability of the supporting structure. It is necessary to ensure that the vertical and horizontal support system is firm, reliable and stable.

[0006] From the above content, it can be known that the jacking construction of the long-span concrete filled steel pipe tied arch bridge across the canal waterway is complicated, difficult, and has high safety risks, and the jacking height is more than 2m, the construction period is short, and the task is heavy. There is no successful experience for reference, and there are few technical materials available for reference

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