| It is generally the opinion of those who have studied and observed corrosion of unbonded post-tensioned cables in heat sealed or push-through cables that the corrosion can be attributed to one or a combination of the following causes:
• Poor quality grease
• Inadequate or “spotty” grease coverage
• Air voids in the sheaths
• Inadequate protection at anchor zones
• Damaged or exposed sheaths
• Exposure to environmental elements prior to installation
The Post-Tech PT Grease Injection system can address all of the aforementioned conditions by using a proven method of re-packing post-tensioned cables. Grease has
been shown to fill the cable voids and to penetrate cracks, defects and porous grout plugs through which moisture can otherwise penetrate. The re-packing of unbonded
post-tensioned cables with corrosion-inhibiting grease provides a cost effective way to prevent or minimize further deterioration. It is recommended that the system be used in conjunction with the PT Cable Drying system to assure that all moisture is purged from the cable sheath.
Features and Benefits
- If a risk of future moisture infiltration exists, then the PT Grease Injection process is utilized to fill voids after cable drying.
- After moisture is expelled with the PT Cable Drying process, rust-inhibiting, Post-Tensioning Institute (PTI) specified grease is injected under high pressure through installed ports or exposed cable anchors.
- Grease has been proven to fill the cable voids and to penetrate cracks, defects and porous grout plugs through which moisture can otherwise penetrate.
- Re-packing unbonded post-tensioned cables with corrosion-inhibiting grease provides a cost effective way to prevent or minimize further deterioration.
- Extends the service life and integrity of structures at a fraction of the cost of other repair methods.
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