21-10-2014, 02:33 PM
Abstracts: Post tensioning will provide information on the successful design of post-tension concrete slabs-on-grade and floors and the effect that performance concrete mix designs have on the success of the finished product. High performance concrete mix designs with low shrinkage, 0.04% or 0.02% @ 28 days for runways, pavements, floors, slabs and toppings are a key component to successful construction of PTSOG. Key elements include a current and accurate concrete specification, low water content, proper w/cm, macro synthetic fibers and optimum essential to verify proper workability, pumpability,finishability setting time. Current nationwide problems are air content above 3% in troweled slabs, retrarded set, excessive cracking or curling, late or improper curing, defensive joint spacing and an over reliance on compressive strength for acceptance.