3D-FE model field-calibration and rating studies on existing r/c buildings

Demirok, Emel
Dynamic instrumentation and a series of ambient vibration tests were performed on a four storey strengthened R/C building within the scope of this study. Traffic load and wind load were accepted as natural dynamic loads and the vibrations were recorded by sensitive accelerometers.For that study, 12 uniaxial, 1 triaxial accelerometers and a 15 channel data logger system were used. Four sets of dynamic measurements were recorded over a period of 6 months. Recorded readings were analyzed using UPC, PC and CVA algorithms and Artemis software. The natural freqeuncies, mode shape of the tested building were determined. The experimental results were compared against each other. A 3D-FE model of the building was prepared and analytical results were also compared against experimental results.The calibration (updating) of the analytical model was carried out using the experimentally obtained mode shapes and freqeunices. The results of the study indicate that first few mode shapes and freqeuncies of the building can be obtained successfully within zero to 10 Hz range using ambient monitoring. Field calibrated FE models can effectively simulate the first translational and torsional modes of the building. Calibration studies indicate that the upper floor is more flexible than the nominal model and there are weaknesses between the shear wall and roof slab connections.


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In this study, relationships between aggregate shape parameters and compressive strength of concrete were investigated using digital image processing and analysis methods. The study was conducted based on three mix design parameters, gradation type, aggregate type and maximum aggregate size, at two levels. A total of 40 cubic concrete specimens were prepared at a constant water-cement ratio. After the compressive strength tests were performed, each specimen was cut into 4 equal pieces in order to obtain the...
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Citation Formats
E. Demirok, “3D-FE model field-calibration and rating studies on existing r/c buildings,” M.S. - Master of Science, Middle East Technical University, 2006.