A Note on Repeated Loading Tests on Components and Complete Structures

Abstract

Summary The purpose of this paper is to describe a method for making repeated load tests and to illustrate several applications of the method. The general characteristics of fatigue testing machines operating on the resonance principle are described, with particular reference to the mode of excitation. A method of excitation different from that in common use is described, and its advantages and disadvantages are explored. Four applications of the new method are instanced. The new method proves particularly applicable to the repeated loading of complete structures and components, because it is readily adaptable to parts of awkward shapes loaded in special ways. Moreover, application of the method is not seriously restricted by large strains of the component under test, nor by moderately heavy absorption of energy by the component. Several further applications of the method to the testing of complete structures are under consideration, and the development of types of fatigue testing machines based on the same method is being explored.