Integral tension, relaxation system and technique for pre-tensioned prestressing tension technique

Abstract

The invention discloses an integral tensioning and relaxation system for pre-tensioning method prestressing technology and a process, which have the advantages of simple construction, material saving, and an accurate exertion of prestressing force value. The integral tensioning and relaxation system comprises a fixed cross beam at a passive end, a prefabricated pedestal, a fixed cross beam at a tensioning end, a movable cross beam, and a pair of jacks arranged between the fixed cross beam at the tensioning end and the movable cross beam. The invention is characterized in that the invention at least comprises one fine bundle spiral steel tool pull rod, and the fine bundle spiral steel tool pull rod is connected with a corresponding working pull rod through a connector for the corresponding working pull rod and a tool pull rod; the working pull rod is connected with a corresponding steel strand through a corresponding steel strand-fine bundle deformed steel bar connector; the other end of the steel strand is then connected with another corresponding working pull rod through the corresponding steel strand-fine bundle deformed steel bar connector; the working pull rod is fixed on the fixed cross beam at the passive end.

Description

technical field [0001] The invention relates to an integral tensioning and releasing system and process for a pre-tensioning prestressed tensioning process. Background technique [0002] With the rapid development of the highway and bridge industry, pretensioned prestressed hollow slabs are welcomed by construction units for their advantages of reasonable design, light components, simple production and transportation, and convenient installation. However, the single tensioning and sand box tensioning techniques currently used are increasingly unsuitable for the production of large-scale prefabricated slab girders. [0003] At present, in the construction of pre-tensioned prestressed hollow slabs, single tensioning and sand box tensioning are generally used. The working principle is shown in figure 1 , it adopts the front clip jack, adopts the construction sequence of symmetrical tension, and applies the initial stress of (10%~20%) δcon steel strand to each steel strand, and...

AI Technical Summary

Problems solved by technology

[0006] (1) Poor economic benefits

[0007] ①The sand box is used for tensioning, and each pedestal must be equipped with two sand boxes, and one moving groove is deep, which increases the project cost

[0008] ②The steel strands between the tension beam and the pedestal are very wasteful

[0009] (2) The stretching time is long, and the operation surface is cumbersome and heavy

It takes about 10 to 15 minutes to stretch each steel strand, and 2 to 2.5 hours to stretch each steel strand. During prestressing, other workers are not allowed to be on the construction site, thus restricting the production of the beam yard. ability

In addition, the use of sand boxes requires work such as loading sand, vibrating, and sanding every time, and the process is too troublesome.

[0011] (3) The stress on a single steel strand is uneven, and the difference in elongation is too large

[0013] (4) poor security

Waste of steel strands, long stretching time, and uneven stress of steel strands are the main factors affecting prestressed tension and release

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