Cascade chart (NDI interval reliability)

<p>A cascade chart is tool that can be used in <a href="/facts/Damage_tolerance/PzaqWudh">damage tolerance analysis</a> to determine the proper inspection interval, based on reliability analysis, considering all the context uncertainties. The chart is called a "cascade chart" because the scatter of data points and downward curvature resembles a <a href="/facts/Waterfall/CDyaLQIQ">waterfall</a> or cascade. This name was first introduced by Dr. Alberto W Mello in his work "Reliability prediction for structures under cyclic loads and recurring inspections". Materials subject to cyclic loads, as shown in the graph on the right, may form and propagate cracks over time due to <a href="/facts/Fatigue_(material)/zmJY8hMt">fatigue</a>. Therefore, it is essential to determine a reliable inspection interval. There are numerous factors that must be considered to determine this inspection interval. The <a href="/facts/Nondestructive_testing/Czz0Vt0B">non-destructive inspection</a> (NDI) technique must have a high probability of detecting a crack in the material. If missed, a crack may lead the structure to a catastrophic failure before the next inspection. On the other hand, the inspection interval cannot be too frequent that the structure's maintenance is no longer profitable.
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Cascade chart (NDI interval reliability) open-in-new

Cascade chart (NDI interval reliability)