Review SessionObjective: Performance through product quality, aswell as effective installation, supervision and inspectionto achieve a successful completion of a project.Note: This review session will not replace the trainingthat an installation/ inspection agency receives.AMSYSCO, Inc. is not responsible for the training of theinstallation crew or individual associated with the fieldinstallation of the post tensioning material.
I. Change in ACI Code• To use an encapsulated system at all locationson a commercial structure.
II. Upgrade of AMSYSCO’s Encapsulated System• No grease at “dead ends” and stressing ends• Grease to be filled in sleeves of intermediateanchors• Plastic sheathing remains intact within theextended sleeve of the anchor– Field labor savings
III. Post Tensioning Field OperationsA. Storage & Handling• Store PT bundles off ground• Cover with tarp• If bundle is shrink wrapped, punch holes inwrapping to allow air circulation• Use nylon slings for handling• Do not drag by “dead end”• All material (PT tendons, anchors, wedges) to bestored in dry environment• Mill certification• Calibration chart of stressing equipment
III. Post Tensioning Field OperationsB. Installation• Attach stressing anchors and intermediateanchors to bulkhead• Position of anchor with regards to bulkhead• Tendons installed in a curve• Anchor/ pocket former• Pocket former and grease – What type ofgrease• Use WD-40
Installation (cont.)• Overlapping anchors• Reverse curvature• Position of support and backup bars• Wobble• Standard friction loss• Can tendon be moved vertically or horizontally?• Can anchor (position) be moved vertically orhorizontally?
III. Post Tensioning Field OperationsC. Stressing• Wedge orientation• Gage pressure – What does it mean?• Position of stressing jack• Location and positioning of pump• Eye contact by pump operator• One-way stressing• Two-way stressing• Multiple pulls (stressing) on the same tendon
Stressing (cont.)• Paint marking (benchmark)• Scale and guide for paint marker• Measurement of elongation• Recording of elongation• Recording of gage pressure• Recording notes in the Elongation Report
Stressing (cont.)• Elongation tolerances• Under elongation• Over elongation• Instant comparison of field elongations vs.mathematical elongations• Decision making if there is deviation andresultant action• Submitting elongation report to the StructuralEngineer of Record
III. Post Tensioning Field OperationsD. Stressing Equipment• Keep equipment dry at all times• Service and maintenance of the stressingequipment• Calibration chart• Safety• Log of service by the operator or contractor’sappointed person
III. Post Tensioning Field OperationsE. Miscellaneous• Hairline cracks in wedges• Strand break– Why strand can break at a lower pressure/ force below theultimate breaking level• Unraveled strand• Kink in strand• Length of electric cord from stressing pump• Stressing equipment and rain• Lift off• Detensioning• When to detension• Overstressing (5%)
A particular slide catching your eye?
Clipping is a handy way to collect important slides you want to go back to later.