Post-Cracking Behaviour of Partially Prestressed Concrete Beams

The treatment of cracking and tension stiffening in serviceability calculations for prestressed concrete is not generally understood by practising engineers and has been inappropriately treated in the draft Australian standard for concrete structures. In this paper, the post cracking service load behaviour of a partially prestressed concrete section is described and analysed. Techniques for calculating flexural rigidity are presented and illustrated by example. The provisions of the new draft standard are reviewed and suggestions for improvement are made. In addition, simple procedures for the estimation of both short term and long term deflections are also presented (a).