  Optimizing inspection and maintenance (I&M) plans for a large deteriorating
structure is a computationally challenging task, in particular if one considers
interdependences among its components. This is due to the sheer number of
possible decision alternatives over the lifetime of the structure and the
uncertainty surrounding the deterioration processes, the structural performance
and the outcomes of inspection and maintenance actions. To address this
challenge, Luque and Straub (2019) proposed a heuristic approach in which I&M
plans for structural systems are defined through a set of simple decision
rules. Here, we formalize the optimization of these decision rules and extend
the approach to enable adaptive planning. The initially optimal I&M plan is
successively adapted throughout the service life, based on past inspection and
monitoring results. The proposed methodology uses stochastic deterioration
models and accounts for the interdependence among structural components. The
heuristic-based adaptive planning is illustrated for a structural frame
subjected to fatigue.
