Simple design formulae for evaluating creep effects in prestressed concrete members

Abstract

Simple design formulae are presented for evaluating the loss of prestress and the flexural deformations (and hence defl ection) that occur in a prestressed concrete member as a result of long-term creep. The closed-form equations are approximate, but are accurate enough for use in preliminary design calculations and possibly also in the detailed design of members that are not deflection-sensitive. The equations are not empirical. They are rationally based and transparent, having been derived from a simplified one-step creep analysis.