An appreciation of the work carried out on fatigue in prestressed concrete structures

Summary A review of the work carried out on fatigue in prestressed concrete is made in this report and observations by the various investigators are included. All the tests show the excellent fatigue resistance of prestressed concrete in the design range of loading. From the review it is apparent that for loadings outside the design range, i.e. after cracking has occurred, the governing factor affecting the fatigue strength of prestressed concrete is the fatigue strength of the high-tensile steel used for stressing. Figures obtained for the fatigue strength of high-tensile wires show that for most types in present use a mean value of 60–65% of the ultimate strength should be taken. No comparable figures for the fatigue strength of high-tensile alloy bars are available. Suggestions are put forward for future research on fatigue in prestressed concrete and the need is emphasized for fundamental research into the behaviour of both high-tensile wires and high-tensile alloy steel bars under fatigue conditions.