Lightweight Concrete for High Strength - Expanded Shale & Clay

strand release, the strand attempts to return elastically to its initial length prior to tensioning. As
the strand becomes shorter, Poisson effects cause an increase in strand diameter creating radial
compression stress between the strand and concrete. The resulting increase in strand diameter
upon release is most pronounced at the free end of the strand and becomes less to a point where
it becomes constant at a distance approximately equal to the transfer length from the end of the
member. After initial end slip at strand release, the resulting frictional bond resistance and
wedge action shown in Figure A.1 restrain the strand and maintain tension in it.
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