Steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method

Abstract

The invention discloses a steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method. The method includes the steps that single steel strands are stretched and drawn through a plurality of pre-tightening devices comprising oil cylinders and pistons; pre-tightening stretching-drawing operation is carried out; oil pressure is measured in real time; when all piston stretching cylinders achieve one stroke, if the pressure does not reach a pre-tightening force set value, automatic returning is carried out for next-stroke pre-tightening till the pressure reaches the set value; if the pre-tightening pressure of any steel strand reaches the set value, a pressure signal is transmitted to a control center through a pressure sensor, the control center controls an overflow valve to be started to maintain the pressure, and after the pre-tightening pressure of all the steel strands reaches the set value, oil is stopped from being supplied to the pre-tightening devices. The method has the advantages that as each pre-tightening jack is of a structure with one oil cylinder and multiple pistons, the integration degree is high, the function of simultaneously and automatically pre-tightening multiple steel strands can be achieved, and the working space is small; for extra-long steel strands, automatic stretching reversing of the jacks can be achieved, continuous pre-tightening is achieved, the speed is high, and the labor cost is low.

Description

Technical field [0001] The invention relates to a construction machine and a construction method for civil engineering, in particular to a method for integral automatic synchronization pretensioning of steel strand group anchor cables. Background technique [0002] In steel strand group anchor cable tensioning, post-tensioning prestressing tensioning, lifting and traction of large components, it is necessary to pre-tighten the pre-stressed tendons or load-bearing tendons, so that each pre-stressed tendon or The load-bearing tendons are basically the same in force before they can be stretched, lifted, and pulled as a whole. The pre-tensioning jack currently in use is a front cassette jack, which has the following defects: [0003] (1) The front jack is used for pre-tensioning, which can only be pre-tensioned one by one. Due to mutual friction between the steel strands, the force of each steel strand will be uneven. Moreover, due to the short stroke of the jack and the long steel s...

AI Technical Summary

Problems solved by technology

[0003] (1) The front clip jack is used for pre-tightening, and only one by one can be pre-tightened. Due to the mutual friction between the steel strands, the stress on each steel strand will be uneven.

Moreover, due to the short stroke of the jack and the long steel strand, it is necessary to manually retension and adjust the jack many times, which is inefficient, labor-intensive, and high-altitude operations increase safety risks;

[0004] Use an ordinary oil pump to provide external force to the jack, and manually operate the oil pump. At the same time, the ordinary jack does not have data collection such as displacement and traction. It is all based on manual readings and manual control, with large errors and risks.

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