Determination of History of Dynamic Stress Intensity Factor at Low Impact Velocities using Reduced Record of Experimental Forces in Three Point Bend Test

The paper examines the possibility of reducing the efforts for data collection through impact testing of three point bend specimens for determining the variation of the dynamic SIF (DSIF) with time. In modelling, the specimen is represented by two Timoshenko beams connected by a rotational spring. The DSIF variation with time is obtained through forced vibration analysis by treating the beam as a free-free system under the action of the experimentally measured striker force and the anvil reactions. The anvil reactions can correspond to any specimen in a batch of specimens differing slightly in length or crack size.