Scaling of input seismic energy of sdof systems through experimental and analytical investigation

Abstract

In this study, two steel hollow section specimens and two aluminum hollow sec tion specimens with different length and cross-sectional dimensions were used. In the analytical part, spectral input energy of these specimens was calculated with ten dif ferent periods under San Salvador, Loma Prieta and Erzincan ground motion records in elastic range. The scale factor for spectral input energy between specimens were calculated with seven different cases in terms of length, cross-sectional dimension and material properties. For each defined binary state, input energy scale factor was deter mined based on material elasticity modulus ratio, length ratio and period ratio between the specimens. In those seven different binary states, spectral input energy values were proportioned and scale factor for input energy was determined. Steel and aluminum specimens’ numerical models were constructed using SAP2000 Structural Analysis soft ware and their corresponding energy values for each period under defined earthquake ground motion were calculated. Spectral energy values were compared with existing mass-normalized input energy spectra (Dindar, 2015) based on earthquake properties. Experimental studies were carried out with four specimens, three different periods and under three different earthquake ground motion records by using shake table. Spectral input energy for each specimen was calculated from the experimental data. Numerical modelling results for spectral input energy values were compared with experimental results and they all showed good agreement. Also, experimental and analytical studies showed that scale factor for spectral input energy is equal to mass scale factor between the specimens for a given ground motion data.