The only way to know how much a new form will shorten is to measure it.
  • Ease the bed into tension to prevent stress or warping the form due to eccentric loading. The goal is to balance the load that is being applied to the form.
  • Tension strands in a symmetrical pattern. Workers performing the tensioning should move from side to side so that the form is tensioned in a balanced manner. When tensioning a double-tee, partially tension one stem. Then move to the other stem, partially tension it, and then move back and forth again until the tensioning is complete. This helps balance the stress applied to the form and could extend its service life.
  • When tensioning a dual, triple, or quad pile form, use the same balancing logic. Workers should partially tension one side, and then move to the other. Repeat the process back and forth until the target is attained.
  • Never pour into one side of a dual form and not the other. If you have a triple pile form and need to pour only one pile, use the center, not one of the ends.
  • In general, tension the lower strands first, then move up.
  • Avoid applying tension to a form that is empty.


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