Damage Identification Analyses of a Historic Masonry Structure in T-F Domain

Fatih mosque, a landmark structure in Istanbul, has suffered structural damage during 1999 Kocaeli earthquake. Using spectral, time-domain (OKID/ERA for SISO and MIMO models) T-F domain (WT, HHT) techniques on ambient vibrations, identification been performed. Results of parametric spectral analyses indicate close global peaks. Northwest arch (O3) that was expected to move harmony with other arches cannot display such consistent behavior produces additional local frequency at 24Hz due damage. Southeast (O1) also comparable producing another locality 38Hz. Extending linear approaches into nonlinear-nonstationary methods, decompositions WT HHT improved the results temporal-frequency energy distribution. Estimated individual are visually inspected states O3 O1. On scale, additionally generates significant nonstationarity neighbors touch. Northeast (O2) is affected strongly by anomalies appeared stations Especially neighbor O6 O7 located springing points others O5 tension rod failure causing dome base open outwards. analysis detects localizes any anomalous system can adequately capture dynamics instrumented part particular time epoch. For historical masonry structures vulnerable components like large central have low redundancy, there need develop automatic signal/image processing through, machine vision, pattern recognition early diagnosis warning gradual deteriorations.