scope:

INTRODUCTION

This Data Item provides crack resistance curve data and a means for estimating the growth of a crack during the application of a given load or for estimating the combination of load and given crack length that will cause fast fracture. Crack resistance curves apply to the macro-growth of a crack during the application of a single load and their principal use is to estimate the static strength of a cracked thin sheet structure. They do not relate to crack growth under cyclic load where growth per load cycle is on the micro scale. However, the most common cause of a crack in a structure is fatigue and crack resistance curves are used to determine the length of a crack propagated by fatigue that is sufficient to cause fast fracture during a single load application. The use of this Data Item is illustrated by two worked examples.