Civil Maintenance Methodology and Susceptibility (Step 7)

Find below additional details for Step 7 of the Civil RBI Methodology.

The Criticality class of a Component (or asset) can also be used as a guideline to determine the type, extent and/or frequency of inspection and/or maintenance tasks for this Component. For instance, if the rate of degradation of a Component is higher than expected (e.g. medium susceptibility) and the consequences of failure are extensive, then it could be justified to monitor the asset and conduct regular upkeep maintenance. If assets are extremely critical, i.e. damage occurs very quickly and consequences are serious, then it would be sensible to redesign (parts of) the asset to make the asset more manageable. At the other end of the criticality spectrum are those assets that are not vulnerable to damage and if they would fail the consequence would be slight. In those instances, it may be justified to let the asset run to failure.

The figure below gives generic maintenance strategies as a function of the criticality. In the actual maintenance plan, it should be worked out in more detail which strategy is acceptable in terms of costs and risks.

Generic maintenance strategies as a function of the criticality.

By default, it is considered that the susceptibility parameter has the default rating of Low.

The risk matrix focuses on the present situation and combines the consequence of failure with the likelihood that the asset or Component would fail in the present year. This matrix reflects a static condition unless something changes regarding the source or type of degradation and should be reviewed from time to time for those changes in degradation sources.