A preloading construction method of assembled 0# block construction bracket

Abstract

The invention discloses a preloading construction method of an assembled 0# block construction bracket, which belongs to the technical field of bridges, and includes installing a 0# block construction bracket, using preloading components to perform preloading and dismantling 0# by adopting a graded tension loading method # Block construction brackets. In the present invention, when the preloading part is tensioned and loaded, the tension end of the steel strand is subjected to the tension stress that is stretched inward along the top wall, and the tension stress acts on the upper longitudinal beam assembly through the limit and direction change of the pulley. The anchorage end of the stranded wire is tensioned downwards to realize the preload. The steel strand is transformed horizontally and vertically, and its length is the stroke from the upper longitudinal beam assembly to the top wall of the bridge pier through the lower reaction beam assembly, which is only related to the length of the upper longitudinal beam assembly and its length to the lower reaction beam The component distance and the length of the lower reaction beam component are related to the distance from it to the top wall of the bridge pier, and have nothing to do with the height of the bridge pier, effectively reducing the stress loss of the steel strand.

Description

A preloading construction method of prefabricated 0# block construction bracket technical field [0001] The present invention relates to the technical field of bridges, particularly a pre-pressing construction method of an assembled 0# block construction bracket. Background technique [0002] The continuous girder bridge superstructure often adopts the construction method of segmental pouring or installation, and finally closing. 0# block is connected The datum block for the first construction of the superstructure of a continuous beam bridge is often cast in-situ directly on the top of the bridge pier by the "bracket method". The 0# construction brackets used in the existing process are all steel components, and their components are usually processed on the construction site or in the factory Production, and finally unified to complete the installation at the construction site. According to the relevant specifications, after the installation of the construction bracket...

AI Technical Summary

Problems solved by technology

[0006] Loading preloading generally requires the preparation of preloading materials (sandbags, concrete prefabricated blocks, water tanks, etc.) in advance, which requires a longer preparation period and a larger stacking site

In addition, all kinds of materials used for pre-pressing are disposable consumables, which will be discarded after pre-pressing, resulting in a huge waste of materials and increased construction costs

[0007] (2) There are many hoisting times and great safety risks

After the preloading is finished, the hoisting equipment is used again to hoist the preloaded materials from the top of the bracket to the ground at the bottom of the pier for unloading. The number of hoistings in the process is extremely large. The impact cannot be ignored. On the other hand, repeated reciprocating hoisting will greatly increase the safety risk in the construction process, especially in the case of high pier, the safety risk will increase exponentially

[0009] (3) The process is easily affected by the environment and climate, resulting in data distortion

It can be seen that the workers staying on the top of the bracket are always in an unsafe working environment

In addition, in the existing process, jacks are used for loading. This loading method is difficult to be integrated and synchronized, and it is easy to cause the bracket to be twisted and deformed, further increasing the safety risk in the process.

[0014] (2) Stress loss is prone to occur, resulting in data distortion

[0016] (3) The appearance quality of concrete is affected

[0017] Before preloading, it is necessary to embed more counterforce devices or their parts with large structural dimensions in some positions of the bridge pier body or on the cap under the pier. After the preloading is completed, use the grinding wheel cutting process or the oxygen cutting process Removing the reaction device will leave a "scar" on the concrete surface of the bridge structure that is difficult to modify, seriously affecting the appearance quality of the concrete

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