Environmental Engineering Reference
In-Depth Information
Future Uptake: Barriers and Facilitators
future uncertainty - whilst achieving maximum
utility when judged against the range of user-
defined objective functions. Practical working
methods can also be reflected and included
within the GA, such as annual budgetary ceil-
ings, or perhaps practical working constraints
such as addressing multiple issues once the work
force is mobilized. The progress of the GA in
finding the best solutions (i.e. ones with higher
net benefits) can be seen by plotting the best
solution found for each generation (Fig. 15.12).
As shown in Figure 15.12 the same optimum
strategy (in this case based on a single objective
function of Nett Benefit) emerges after around
60 generations.
The introduction of formal and structured risk-
based approaches to asset management chal-
lenges many traditional ideas and can be difficult
to achieve in practice. Many of the barriers to
the uptake of such methods reflect capacity to
adopt new approaches, misconceptions around
the complexities of risk-based methods and
the challenge of converting good science into
practical usable tools. The science and practice
of asset management need to go hand in hand -
with one evolving from the other. The capacity
for change is limited (in both skills and support-
ing infrastructure) and the scientific demand for
changemust be commensuratewith the practical
benefits afforded by that change. Simple illustra-
tions and pilot studies that explain the complex
scientific processes in practical terms are a
vital aid in building understanding in the user
community
Review, Decide and Act
and
avoiding mistrust
and
Asset management tools seek to provide evidence
in support of decisions, but not, of course, to
make decisions. Expert judgement and engineer-
ing skill will continue to feature strongly
throughout the asset management process - from
the input data through to confirming the preferred
course of action. Incorporating the expert judge-
ment in an unbiased and transparent manner is
problematic. Considerable progress has been
made in recent years to integrate expert judge-
ment and quantified analysis tools (Simm
et al. 2008; Hall and Solomatine 2008). In partic-
ular expert judgement can be used to validate
model inputs and provide credibility to (and
validation of) the outputs from the analysis. The
decision-maker also needs to be confident that
the decision made is robust to the uncertainty
in the data, the predicted impact of the action
(e.g. reduced risk) and the associated cost (e.g.
whole-life costs and benefits). Quantified uncer-
tainty propagation methods (Gouldby et al. 2010)
together with multi-criteria decision-making pro-
vide efficient methods to support the decision-
maker in identifying robust choices. Although
these are interesting and important areas they are
not discussed further in this chapter.
misconception.
Conclusions
The implementation of risk-based asset manage-
ment reflecting whole-life performance will de-
mand close collaboration between the science
community and engineering practice. To be suc-
cessful there are a myriad of activities that will
need to be integrated and coordinated within and
outside of those organizations with a direct inter-
est inmanaging flood defence assets. As this chap-
ter highlights, system analysis, reliability, risk
attribution and optimization techniques do, how-
ever, provide a number of important insights and
aids to the decision-maker.
The RELIABLE analysis tool provides a flexible
and practical means to analyse the reliability of
most structures. The results fromRELIABLE have
been shown to be credible and easy to apply,
enabling high-level generic fragility curves to be
replaced (within the system analysis models)
where the need is greatest.
An understanding of an asset's chance of failure
(now and in the future)
is an important
