Experimental study of sensitivity-aided application of artificial boundary condition frequencies for damage identification

This paper presents an experimental study on the application of the so-called artificial boundary condition (ABC) frequencies for structural damage identification. Aided by the corresponding sensitivity analysis, more suitable ABC frequencies can be selected for improved identification of structural damage. An overview of the theoretical background of ABC frequencies and their sensitivity formulation is provided first. An experimental programme involving model steel beams in the intact and damaged states for the measurements of ABC frequency is presented, and the extraction of the ABC frequencies is descried and discussed. The extracted ABC frequencies are selected in accordance with the sensitivity analysis and they are subsequently employed to identify the structural damage. Results demonstrate that, aided by the sensitivity-based selection procedure, the ABC frequencies can be used for practical identification of structural damage and both the damage location and severity can be determined with good accuracy.