Fatigue of Periodically Overloaded Stiffener Detail

by Ali Abtahi, Former Grad. Asst.; Dept. of Civ. Engrg., Univ. of Maryland, College Park, Md.,
George R. Irwin, Visiting Prof.; Dept. of Mech. Engrg., Univ. of Maryland, College Park, Md.,
Pedro Albrecht, (M.ASCE), Assoc. Prof.of Civ. Engrg.; Univ. of Maryland, College Park, Md.,


Serial Information: Journal of the Structural Division, 1976, Vol. 102, Issue 11, Pg. 2103-2119


Document Type: Journal Paper

Abstract: The effect of periodic overloads on enhancement or delay of fatigue crack initiation and propagation at a transverse stiffener detail is investigated. A total of 73 specimens fabricated from A588 steel were tested. The overloading conditions were: (1)No overloads; (2)one overload applied at the beginning; and (3)six cases in which overloads were applied every 106 to 10 constant amplitude cycles. The ratio of overload to the loads applied during constant cycling was 1.67. Overloads applied every 10³ cycles or farther apart extended life with the longest delay occuring at a spacing of about 105 cycles. The transition from delay to enhancement of fatigue cracking occurred at 10² cycles. Reasons for delay effects on fatigue crack initiation and propagation are presented.

Subject Headings: Overloads | Fatigue (material) | Cracking | Stiffening | Fabrication | Steel | Load factors | Lifeline systems

Services: Buy this book/Buy this article

 

Return to search