Structural integrity monitoring index (SIMdex): a methodology for assessing structural health monitoring technologies

Recent years have seen enormous activity in the development of structural integrity monitoring/structural health monitoring equipment and systems. Systems based on technology that could in the past have only been used under laboratory conditions are now frequently deployed in the field very often claiming accuracy and reliability commensurate with laboratory measurements. Monitoring is certainly an exciting prospect and has many advantages over traditional NDT; there are, however, some very fundamental issues that must be resolved to benefit fully from these new technologies. Not least of these is the development of objective measures to quantitatively assess the performance characteristics of monitoring technologies. This article presents the background and development of such a measure of performance based oil fatigue and fracture mechanics failure models of the host structure. This new measure, the structural integrity monitoring index or SIMdex, can be similarly applied using any failure model and criterion and means that structural integrity monitoring technologies can be objectively judged solely on their suitability for specific applications.