Fatigue Strength of Intersecting Attachments

Abstract

Experimental investigations are carried out on intersecting attachments to investigate their fatigue strengths. Two types of intersecting attachments are studied, i.e., the T type with one longitudinal attachment intersecting a transverse stiffener at one end, and the H type with a longitudinal attachment intersecting two transverse stiffeners at both ends. The length of the longitudinal attachment in the T type is changed to study its effects on fatigue strength. The scalloped version of the specimens, free of welds at the intersection of the transverse and longitudinal attachments, is also investigated. Test results show that the fatigue strength of the T type attachment is comparable to that of the single longitudinal attachment. The fatigue strength of the H type attachment is in between those of the single longitudinal and transverse attachments. The introduction of the scallops does not influence fatigue strength significantly, but results in a change in the locations of fatigue cracks in the H type attachments. The method suggested by the writers for fatigue strength evaluation of weld toe failures is demonstrated as suitable for evaluating fatigue strength of intersecting attachments.