Construction Method of Variable Height Steel Beam by Lifting and Pushing Brackets

Abstract

The invention discloses a variable-height girder construction method for the construction by using a hoisting and pushing bracket. The variable-height girder construction method comprises the following steps of 1, prefabricating girder segments, and erecting an assembling platform; 2, assembling a first hole girder, meanwhile, mounting the hoisting and pushing bracket, arranging T-shaped steel on the top flange of the girder between rollers at the top of the hoisting and pushing bracket in a penetrating manner to perform forward hoisting and pushing; 3, before the first hole girder arrives at a third pier, completing the construction of the hoisting and pushing bracket at the third pier, assembling a second hole girder connected with the tail of the first hole girder on the assembling platform to realize the continuous hoisting and pushing of the girder; 4, constructing the rest of cross girders and hoisting and pushing brackets at the tops of the other of pier according to the step 3 until the first hole girder is mounted on the pier at the tail end of a bridge, thereby completing the girder erecting operation of the whole bridge; and 5, dismounting the assembling platform and the hoisting and pushing bracket to complete the construction. The construction of a variable-height girder can be simplified, the construction period is shortened, and the construction cost is reduced.

Description

technical field [0001] The invention relates to the technical field of steel beam construction, in particular to a construction method for variable height steel beams constructed by lifting and pushing brackets. Background technique [0002] At present, the jacking method is mostly used in the construction of steel beams at home and abroad. However, the jacking method is more suitable for equal-height beams with small spans; when the span of the bridge increases, variable-height beams are used in order to save steel consumption. Or the way of setting special devices to meet the change of beam height. [0003] The former is to flatten the bottom of the variable-height beam body with wedge-shaped blocks, and then push it according to the method of equal-height beams. This method is cumbersome to operate, has low precision, and slow construction speed. Low reuse rate. The latter mostly adopts the hinged method to allow the beam body to rotate during the pushing process. For ...

AI Technical Summary

Problems solved by technology

This construction method has the following disadvantages: 1. During the jacking process, the bottom plate of the beam body is almost entirely affected by the local load of the fulcrum, and local instability is prone to occur; 2. In order to avoid the problem of local instability, more measures need to be added, resulting in project cost 3. The elevation of the end of the steel girder changes constantly, and the amplitude is too large, making it difficult to maintain the level of the bridge deck; 4. The steel girder cannot be continuously pushed; 5. The construction speed is slow due to the continuous change of the bridge posture during the construction process; 6. The construction process of the cantilever is long, and the risk of the bridge is high

[0004] It can be seen that the construction of variable cross-section steel-concrete composite girder bridges using the jacking method has technical problems such as complex on-site operation procedures, low construction safety factor, discontinuous construction, and the need for auxiliary processes, which affects the promotion of variable cross-section steel-concrete composite girder bridges. application

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