Construction method for negative pressure vacuum supplementary grouting of vertical prestressed duct of continuous beam
By installing T-junctions and vacuum pumps in the prestressed ducts to perform negative pressure vacuum grouting, the problems of incomplete grouting and corrosion fracture caused by blockage of the prestressed ducts were solved, achieving smooth grouting and improving the construction quality and service life of the bridge.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CCCC THIRD HARBOR ENG CO LTD NINTH ENG CO LTD
- Filing Date
- 2024-01-30
- Publication Date
- 2026-06-26
AI Technical Summary
In existing technologies, when prestressed ducts are blocked and lack ventilation holes, incomplete grouting or grout leakage can lead to corrosion and breakage of prestressed tendons in the later stages, and make grouting difficult, affecting the construction quality and service life of bridges.
The method of negative pressure vacuum supplementary grouting for vertical prestressed ducts of continuous beams is adopted. By installing equipment such as tee pipes, ultra-high vacuum pumps and manual grouting pumps, micro-expansion fast adhesive is used to seal the gaps, vacuum degree test and water injection test are carried out, uniform cement grout is prepared, and negative pressure is used to achieve smooth flow of grout in the duct.
This ensures smooth flow of grout within the grouting pipe, avoids grouting difficulties, guarantees the grouting quality of the prestressed duct, and improves the construction quality and service life of the bridge.
Smart Images

Figure CN117867986B_ABST