PT encapsulation: greased sleeves?
PT encapsulation: greased sleeves?
(OP)
I have provided the backup info below and here's the question: On encapsulated PT sysyems are the transition components, the plastic translucent sleeves, at anchorages suppose to be filled with grease or not? The engineer at the PT company claims that filling the sleeves with grease is a "PTI certified plant recommendation" and not a "requirement". Is he pulling my leg?
ACI-318-05 18.16 Corrosion Protection for Unbonded Tendons
Code = 18.16.4 — Unbonded single strand tendons shall be protected against corrosion in accordance with ACI’s “Specification for Unbonded Single-Strand Tendons
(ACI 423.6).
Commentary = R18.16.4 — In the 1989 code, corrosion protection requirements for unbonded single strand tendons were added in accordance with the Post-Tensioning Institute’s “Specification for Unbonded Single Strand Tendons.” In the 2002 code, the reference changed to ACI-423.6.
ACI-318-05 3.8.4 — “Specification for Unbonded Single Strand
Tendons (ACI 423.6-01) and Commentary (423.6R-
01)” is declared to be part of this code as if fully set
forth herein.
So when I look in ACI-423.6-01 I read:
2.3.5 — Aggressive environments
The sheathing connection to sleeving at couplers and
to all stressing-end, intermediate, and fixed-end
anchorages shall be watertight and free of air spaces.
2.2.6.2 — Sleeves used to connect the sheathing to
the anchorage of encapsulated systems shall:
e) Be translucent or have another method of
verifying that the post-tensioning coating
material is free of voids; and
Commentary:
R2.2.6.2 — The requirements that prohibit voids may be
satisfied by filling the sleeves with post-tensioning coating. Transition components at anchorages and couplers should be designed to be void-free.
ACI-318-05 18.16 Corrosion Protection for Unbonded Tendons
Code = 18.16.4 — Unbonded single strand tendons shall be protected against corrosion in accordance with ACI’s “Specification for Unbonded Single-Strand Tendons
(ACI 423.6).
Commentary = R18.16.4 — In the 1989 code, corrosion protection requirements for unbonded single strand tendons were added in accordance with the Post-Tensioning Institute’s “Specification for Unbonded Single Strand Tendons.” In the 2002 code, the reference changed to ACI-423.6.
ACI-318-05 3.8.4 — “Specification for Unbonded Single Strand
Tendons (ACI 423.6-01) and Commentary (423.6R-
01)” is declared to be part of this code as if fully set
forth herein.
So when I look in ACI-423.6-01 I read:
2.3.5 — Aggressive environments
The sheathing connection to sleeving at couplers and
to all stressing-end, intermediate, and fixed-end
anchorages shall be watertight and free of air spaces.
2.2.6.2 — Sleeves used to connect the sheathing to
the anchorage of encapsulated systems shall:
e) Be translucent or have another method of
verifying that the post-tensioning coating
material is free of voids; and
Commentary:
R2.2.6.2 — The requirements that prohibit voids may be
satisfied by filling the sleeves with post-tensioning coating. Transition components at anchorages and couplers should be designed to be void-free.






RE: PT encapsulation: greased sleeves?
RE: PT encapsulation: greased sleeves?
ACI-423 2.3.5 — Aggressive environments
The sheathing connection to sleeving at couplers and
to all stressing-end, intermediate, and fixed-end
anchorages shall be watertight and FREE OF AIR SPACES.
I spoke with engineers at two different PT companies today and both said that the air space in the sleeve is only filled with grease if the SER specifies "void-less encapsulation".
My question is if the SER cites ACI-318 in the specs and 318 sets ACI-423 as the standard how does a sleeve filled with air equal "free of air spaces"? Isn't that tantamount to telling the SER who cites a code in the specs that he/she is required to repeat that code in the specs word-for-word and then say "yes, I really want that stuff."
RE: PT encapsulation: greased sleeves?
Am I on to something or just way off base?
RE: PT encapsulation: greased sleeves?
RE: PT encapsulation: greased sleeves?
Same as near as i can tell.
RE: PT encapsulation: greased sleeves?
Remember the discussion we had on a similar topic a while back? http://www.eng-tips.com/viewthread.cfm?qid=143186
RE: PT encapsulation: greased sleeves?
RE: PT encapsulation: greased sleeves?
RE: PT encapsulation: greased sleeves?
He also said that PTI was aware that producers are sending out phony-baloney submittals and shop drawings that depict greased sleeves but no greased sleeves are actually shipped to the job.
RE: PT encapsulation: greased sleeves?
Just started a high-rise job and the parking deck has encapsulated PT. The owner apparently specifically requested encapsulated PT in the parking deck. So during the concrete pre-con meeting the special inspector has the absolute gaul to bring up the various requirements of ACI423.6 with regard to encapsulation. To our amazement the PT arrived at the job with the fixed end anchors having greased sleeves. Then the game of everyone pretending that no one knew how to field fill the intermediate and live end anchor sleeves ensued.
The logic of a) the spec requires it and b) the fixed end is greased so why wouldn't the other end be greased seemed not to matter.
But then to our further amazement a magical machine arrived at the job! It's nothing but a little pneumatic grease pump that sits atop a 5 gallon buck of PT grease with a grease gun with a long syringe: stick syringe up sleeve, pull trigger, slowly pull syringe out, place rubber grommet.
I took some pics of the machine so that at the next job when everyone goes into denial/obfuscation mode I can pull them out and thwart mediocrity.