Stressing Tendons with Short Tendon Tails

In certain situations, the tendon tail of an unbonded post-tensioning tendon may be too short to stress with the hydraulic jack.  With the standard nose piece, the PT stressing operator would need around 13 inches of tendon tail (outside the concrete) in order to stress the tendon without any modification to the hydraulic jack.  If the tendon tail is between 4 inches and 13 inches, one modification to the hydraulic jack is to take the nose piece off and install two “jack feet.”  The jack feet act as bearing surfaces between the concrete slab and each hydraulic piston.  The installation takes around one minute and the procedures are as follows:

Stressing Jack with nose piece

Stressing Jack with nose piece

 

Untighten screws to disassemble nose piece

Loosen screws to disassemble nose piece

 

Stressing Jack without nose piece

Stressing Jack without nose piece

Stressing Jack with jack feet

Stressing Jack with jack feet

Disclaimer:  For safety reasons, stressing tendons with jack feet should be carried out by qualified and experienced personnel.

– Neel Khosa, Vice President

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Copyright © 2013 by AMSYSCO, Inc. All rights reserved.

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