  The maturity of structural health monitoring technology brings
ever-increasing opportunities for geotechnical structures and underground
infrastructure systems to track the risk of structural failure, such as
settlement-induced building damage, based on the monitored data. Reliability
updating techniques can offer solutions to estimate the probability of failing
to meet a prescribed objective using various types of information that are
inclusive of equality and inequality. However, the update in reliability can be
highly sensitive to monitoring location. Therefore, there may exist optimal
locations in a system for monitoring that yield the maximum value for
reliability updating. This paper proposes a computational framework for optimal
monitoring location based on an innovative metric called sensitivity of
information (SOI) that quantifies the relative change in unconditional and
conditional reliability indexes. A state-of-the-practice case of risks posed by
tunneling-induced settlement to buildings is explored in-depth to demonstrate
and evaluate the computational efficiency of the proposed framework.
