Two arm-brace stretching method of arc bridge tie bar cable

Abstract

The invention discloses a two arm-brace stretching method of an arc bridge tie bar cable, comprising the following steps of: sequentially installing a working anchor, a working anchor arm brace, a rear tool anchor, a tool anchor arm brace, a hydraulic jack and a front tool anchor, enabling the working anchor and the rear tool anchor in a loosening state, clamping a prestressing steel strand by using the front tool anchor and stretching an oil cylinder by using the hydraulic jack to feed oil and pushing the front working anchor for stretching the prestressing steel strand; stopping the stretching of the oil cylinder by using the hydraulic jack to feed oil when the hydraulic jack reaches the maximum stroke, clamping the prestressing steel strand by using the rear tool anchor to enable the front tool anchor to be in a loosening state and stretching the oil cylinder by using the hydraulic jack; carrying out next round of stretching operation after stretching the oil cylinder by using the hydraulic jack to return oil in place; and clamping the prestressing steel strand by using the working anchor when the prestressing steel strand reaches the requirement. In the stretching process, a working clamping piece of the working anchor is not forced, thus the invention solves the problems that the work clamping piece of the working anchor is repeatedly forced and teeth are blocked in the stretching process of a long steel strand cable in the prior art and prolongs the service life of the working anchor.

Description

Technical field [0001] The invention relates to the technical field of bridge building construction, in particular to a double-leg tensioning method for arch bridge tie rod cables. Background technique [0002] Conventional steel strand and long cable tensioning process uses a set of tool anchors and a set of working anchors to cooperate with each other to tension the steel strand long cables. For long cables, the jack stroke cannot be achieved because the elongation of the prestressed steel is greater than the jack stroke. Once the tension is in place, it often takes several times of "topping" to complete the tensioning of the prestressed beam. When the "topping" operation is completed, the working clamps of the working anchor are repeatedly anchored, which affects its normal anchoring performance, and As the prestressed steel is scratched, the skin or coating of the steel strand will block the teeth of the working clamp, which further reduces the anchoring performance of the wo...

AI Technical Summary

Problems solved by technology

[0003] In view of this, the object of the present invention is to provide a kind of arch bridge tie-rod cable double-leg tensioning method, the working clip of the working anchor is not stressed during the tensioning process, which solves the problem of the steel strand long cable tensioning process in the prior art. The working clip of the working anchor is repeatedly stressed and the teeth are blocked, prolonging the service life of the working anchor

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