Methods of determining the margin of cyclic crack resistance of metal structures for hoisting machinery

摘要

In the course of manufacturing and operation, there can appear cracks in load-carrying metal structures which are hard to be detected till a definite moment. That is why in the course of designing metal structures, it is necessary to ensure their durability during possible existence of cracks up to the next routine inspection of a structure. For the prognostication of the durability of a structure with a crack, a research of coefficients of stress intensity on end-element models with crack-like defects of different length is carried out. As a result of this, a procedure for the definition of crack-resistance resource allowing the supposition of safe operation of a metal structure with a crack within the limits of recurrent routine works is developed.