A Fatigue Study of Prestressing Strand

Strand fatigue data reported in the literature and also from recent tests were combined to form a data base of strand fatigue data which was analyzed using regression analysis techniques. A stress range vs. fatigue life curve for prestressing strand was developed and was used as the basis for a strand fatigue design equation. The design equation was compared with AASHTO Code provisions for fatigue of structural steel and was found to lie midway between Category A and Category B curves for redundant structures. Category B is recommended for checking the allowable fatigue stresses in uncracked girders and strand tension systems when considering the life of the strand.