Low-retraction prestressed anchorage device and tensioning method

Abstract

The invention discloses a low-retraction prestressed anchorage device. The low-retraction prestressed anchorage device comprises a work anchorage plate, work clips and a pressure-bearing nut. Comparedwith common anchorage devices, the retraction amount of a steel strand in the tensioning construction can be reduced, and the loss of prestress can be reduced; and compared with existing low-retraction anchorage devices, the low-retraction prestressed anchorage device has the advantages of saving work anchorage plate materials and being convenient to process. According to a tensioning method of the low-retraction prestressed anchorage device, the length of a brace angle is spirally adjusted after first-time tensioning, then second-time tensioning is carried out, and the retraction amount of the steel strand during first-time tensioning is eliminated by spirally adjusting the pressure-bearing nut; and there is no need to disassemble a jack, mount the brace angle, mount a pull rod and the like between first-time tensioning and second-time tensioning, the tensioning process is greatly simplified, and the tensioning construction operation is facilitated.

Description

technical field [0001] The invention relates to the technical field of prestressed anchors, in particular to a low-retraction prestressed anchor and a tensioning method. Background technique [0002] Prestressing technology is widely used in prestressed concrete structures. Prestressing technology can offset or reduce the tensile stress of concrete structures caused by external loads to ensure structural safety. In the steel strand clip anchorage system, there is a situation in which the prestress of the system is lost due to the release of tension and the retraction of the steel strand during construction. In particular, the prestress loss caused by the retraction of the steel strands in the short-bundle steel strand clip anchorage system is greater. [0003] The low-retraction anchor can greatly reduce the prestress loss of the system caused by the tension and the retraction of the steel strand. The common low-retraction anchors currently used in engineering are composed...

AI Technical Summary

Problems solved by technology

[0004] The anchor plate used in the above-mentioned ordinary low-retraction anchorage is an anchor plate with full external thread, and the anchor plate is thicker than the anchor plate of ordinary anchorage, and the material cost increases; with full external thread, it is difficult to clamp and process, and the processing cost increases

The above-mentioned low-retraction anchorage tensioning method requires two tensions, and requires the installation and removal of jacks, bracing angles, and tie rods. The work content is cumbersome and troublesome, and the construction efficiency is low.

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