Real data and numerical simulations-based approaches for estimating the dynamic characteristics of a tunnel formwork building

Abstract

Due to their expected high seismic resistance, a significant number of tunnel formwork buildings have been built over the past few decades, especially in regions of high seismic hazard. However, only few real data analyses have been reported and are available so far. Different techniques, including real data analysis, numerical simulations, and their combination, are employed to investigate and compare their potentials for estimating different aspects of a tunnel formwork building. This study is based on data from a 16-story residential building in Istanbul, Turkey. The real data analysis of the building’s dynamic characteristics is based on both the vibrational (spectral analysis) and waveform (deconvolution interferometry) approaches, which yield information on the soil–structure system and the fixed-base building. For this purpose, dense ambient vibration/generated source measurements and earthquake recordings of both temporary and permanent networks are used. Furthermore, finite element analysis (FEA) of the building is carried out. The order of the first bending and torsional modes is reversed in the results of the numerical simulations compared to those from the real data. This can be attributed to the simplifications and assumptions made in the numerical simulations of tunnel formwork structures. It emphasizes the importance of analyzing real data for better constraining numerical simulations. Finally, the response of the building (synthetic seismograms) to a real data input is calculated using FEA. Deconvolved wavefields of synthetic and the real data are estimated. Despite the changed order of the modes, the deconvolved wavefields for both cases match very well.