History of the Post-Tensioning Manual

Currently, the Post-Tensioning Manual is in its 6th Edition (2006, first printing) and is published by the Post-Tensioning Institute (Technical Advisory Board committee).

The Prestressed Concrete Institute (Post-Tension committee) published the 1st edition of the Post-Tensioning Manual in 1972.  Thereafter, the Post-Tensioning Institute published the 2nd edition in 1976, the 3rd edition in 1981, the 4th edition in 1985 and the 5th edition in 1990 (with its fifth printing of the 5th edition in 2000).

The previous version of the PT Manual (5th Edition) had more of a “marketing feel” compared to the current edition.  It was released due to the advent of the 1989 version of ACI-318 Code.  Below is a short excerpt from the Introduction which gives some historical contention of the birth of post-tensioning.

Further development of post-tensioning was interrupted by World War II.  However, the shortage of steel in the post-war years gave impetus to the use of prestressed concrete in replacing war damaged bridges throughout much of Europe.

The Manual included sections on the following:

  • Applications of Post-Tensioning
  • Post-Tensioning Systems (by company/supplier)
  • PT Specifications
  • Recommendations for Prestressed Rock and Soil Anchor (more information in a separate PTI manual)
  • Analysis & Design of Post-Tensioned Structures (more information in separate PTI manuals).
  • Detailing & Construction Procedures
  • Fire Resistance of Post-Tensioned Structures.

The Post-Tension-Manual-5th-Edition-Amsysco PDF File (downloadable, 1MB) includes an excerpt from the old 5th Edition which promotes AMSYSCO, Inc. and its product at the time.  You’ll notice our old headquarters in Addison, IL and a sample project listing.

– Neel Khosa, AMSYSCO
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Copyright © 2010 by AMSYSCO, Inc. All rights reserved.
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Field-Seating Fixed End Anchor

Occasionally, an ironworker will need to “field-seat” a fixed-end anchor to an unbonded post-tensioning tendon.  This may be required for the following reasons:

  1. Lack of stressing access on one side of a double-end stressed tendon.
  2. Incorrect tendon configuration at elevation differences (ex. parking ramps)

If an ironworker is in one of these situations, then they must use the proper equipment to safely affix the anchor to the strand.  The ironworker will need the following post-tensioning parts:

  1. Tendon (PC strand with plastic sheathing taken off)
  2. Anchor
  3. Wedges
  4. Encapsulation accessories (if required)
  5. Hand-seating Tool
  6. Bearing Plate
  7. Detensioning Tool
  8. Stressing Equipment (calibrated jack, pump, gauge)

Equipment from left to right: Anchor with Strand (black), Bearing Plate (silver), Detensioning Tool (white) and Stressing Jack (green)

An ironworks who is certified in stressing post-tensioning tendons should be able to field-seat the fixed end anchor.  Refer to picture above for the correct setup.  The gauge pressure on the stressing equipment will the same as that for a normal stressing operation (at 33 kips).  Also, the correct length of strand past the anchor is required in order to attach the yellow snap cap to end of the strand (see picture above with “encapsulated system – pull method”).

Failure to use the proper parts or equipment could result in damaging the anchor, strand, equipment or harming the operator/by-standers.  This procedure should be carried out by a Post-Tensioning Institute Certified Ironworker (level 2).

– Neel Khosa, Vice President, AMSYSCO

Watch the Video:  https://amsyscoinc.com/2012/08/01/video-field-seating-anchor/
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Copyright © 2010 by AMSYSCO, Inc. All rights reserved.
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PTI Certified Plant – Amsysco 2010

AMSYSCO, Inc. passed its first unannounced Plant Inspection in May 2010 conducted by the Post-Tensioning Institute.  A copy of the current PTI certification can be viewed PTI-Plant-Inspection-2010.01-–-Amsysco HERE.

Related Links:  AMSYSCO Certified Plant for past year’s certificates (1989-2009)


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Copyright © 2010 by AMSYSCO, Inc. All rights reserved.

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