Prestressed intelligent circulation grouting system and its control method

Abstract

A prestressed intelligent circulating grouting system and its control method, the grouting pipeline between the grouting pump and the grouting port is provided with a pressure compensation device, the pressure compensating device includes a piston and an elastic mechanism, and the piston end The head is connected with the grouting pipeline, and the elastic force of the elastic mechanism is to drive the piston end to press into the grouting pipeline; the pressure maintaining devices are respectively installed at the slurry inlet and the slurry outlet, and respectively control the amount of slurry entering the channel of the beam member and the discharge The amount of slurry in the channel of the beam member; the electromagnetic flowmeter is respectively installed at the slurry inlet and the slurry outlet to measure the flow signals of the slurry inlet and the slurry outlet; The grouting action, the water-cement ratio control step adopts closed-loop control, and the effective cycle pressure value is set; the holding pressure value: the lower limit value of the holding pressure; the upper limit value of the holding pressure; the holding time value controls the component slurry control. Its advantages are stable slurry pressure, compact grouting and good component quality.

Description

technical field [0001] The invention relates to the technical field of prestressed engineering, in particular to a prestressed intelligent circulation grouting system and a control method thereof. Background technique [0002] During bridge construction, the quality of prestressed grouting construction is crucial to the safety and durability of prestressed bridges, so post-tensioning prestressed pipeline grouting construction has become a key process in prestressed bridge construction. [0003] Chinese patent CN103711315 discloses a patent titled "Intelligent Vacuum Circulation Grouting System". In order to solve the problem of unstable grouting quality in traditional grouting systems, this patent adopts a technical scheme of setting a program-controlled three-way valve in the grout return pipe. The quality of grouting, but because the pressure of the grout changes during the transmission process, the grouting quality at some positions of the grout is unstable. [0004] Chi...

AI Technical Summary

Problems solved by technology

[0003] Chinese patent CN103711315 discloses a patent titled "Intelligent Vacuum Circulation Grouting System". In order to solve the problem of unstable grouting quality in traditional grouting systems, this patent adopts a technical scheme of setting a program-controlled three-way valve in the grout return pipe. The quality of grouting, but because the pressure of the grout changes during the transmission process, the grouting quality of the grout part is unstable

[0004] Chinese patent CN103711316 discloses the title: "Control Method of Intelligent Pulping System". The control of the patent is to control the weight of the main material and the auxiliary material separately. The control process is open-loop control. The final slurry water-cement ratio It is impossible to carry out more detailed control; and only one grouting pump is used, and only the holding pressure value is set in the automatic grouting step. The control method adopted is that if the pressure value drops below the pressure standard value during the holding period, the control center sends Grouting command, grouting again, until the pressure standard value is reached before maintaining the pressure, this method cannot effectively control the quality of grouting, resulting in unstable grouting quality

[0005] Due to the lack of strict control of the water-cement ratio (water-cement ratio is the main performance parameter of the slurry) in the traditional grouting process, the flow performance is often improved by increasing the water consumption on site, which eventually leads to excessive bleeding rate, forming voids in the pipeline and bleeding Free water, which accelerates the corrosion of steel strands

[0006] These problems existing in the above-mentioned traditional grouting process will seriously affect the durability of the structure. First, the steel strands lose their protection and are prone to corrosion. The corrosion of the tendons further weakens the bonding force of the slurry to the tendons, resulting in effective prestress drop

Second, there is a void in the pipeline, which prevents the steel strand and concrete from forming a whole to work together, reducing the structural rigidity and bearing capacity

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