Structural health monitoring of a tall building

Abstract

In mega cities such as Istanbul, tall buildings are inevitable outcomes of limited construction areas; however in earthquake prone mega cities again such as Istanbul, adequate precautionary measures for tall buildings must be taken before and after an expected earthquake. Structural health monitoring techniques have been used to understand existing conditions of structures, as well as their post-earthquake conditions. In order to investigate possible solutions to such necessities, a twenty-six story, core-wall tall building in Istanbul is instrumented with sixteen accelerometers. Natural frequencies and modal shapes of the building are obtained by frequency domain decomposition method. These results are compared with the modal values obtained from the finite element model of the building created according to design drawings. A finite element model updating process is applied. Time history analyses under probable earthquake input motions are performed. Analyses results are compared based on probability density functions. In this study it is shown that model updating based on identified modal values are significant in the determination of seismic demands on tall buildings.