Structural modeling uncertainties and their influence on seismic assessment of existing RC structures

The structural modeling uncertainty may be comparable to that of the ground motion representation in the seismic assessment of existing buildings. This work aims to characterize the uncertainties in material properties and in construction details and to propagate them to estimate the structural performance conditional on code-based seismic demand and capacity definitions. A prior probability distribution for the uncertain parameters is constructed based on the state of knowledge about the building before any in situ test is conducted. The uncertainties in the parameters are then propagated using simulation in order to obtain a probability distribution for structural resistance. The simulation-based methods allow for suitable grouping of uncertain parameters in order to build a simplified model of correlation across structural parameters. The results of tests and inspections are used both to update the prior probability distributions for parameters and also to update the structural reliability in a Bayesian framework. The updated probability distributions take into account the increased level of information eventually gathered as a results of destructive and/or non-destructive tests and inspections on the structure.