Evaluation of expected life-cycle cost of structures using structural health monitoring

In recent few years Structure Health Monitoring (SHM) technologies have emerged as a promising tool for an enhanced assessment of a structure's condition in terms of its performance, capacity and the state of degradation. Indeed, SHM furnishes nothing but information. Intuitively, of course, this information provides value. In this study, an attempt is made to calculate the value of such information. The frequency and timeline of the application of inspection and maintenance actions (interventions) and their duration depend on a number of parameters, values of which are often uncertain or random. SHM information can be used for reducing the uncertainties associated with the parameters that influence the repair/maintenance decisions. If a structure is equipped with an SHM system, the probability of the first intervention as assumed based on past experience with similar structures can be updated using the observed performance of the structure. This updated probability is used to evaluate the expected probability of maintenance at a certain time or age, which is then used for determining the expected life-cycle maintenance cost. An existing steel free deck continuous bridge is analyzed to illustrate the proposed methodology and to reveal the value of information. Results show that SHM system can be very useful to decision makers as it supplies superior information regarding the performance of structure. Because of the limitation of space, only key results have been presented in this paper.