Inelastic condensed dynamic models for estimating seismic demands for buildings

• Published in: Engineering structures Vol. 177; pp. 616 - 629
• Main Authors: Tehrani, M.H., Harvey, P.S., Gavin, H.P., Mirza, A.M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.12.2018; Elsevier BV
• Subjects: Accuracy; Aseismic buildings; Bouc–Wen model; Computer applications; Computer simulation; Dynamic models; Earthquake engineering; Earthquakes; Finite element analysis; Finite element method; Ground motion; Hysteresis; Iterative methods; Mathematical models; Model reduction; Response history analysis; Seismic activity; Seismic demand; Seismic engineering; Simulation; Structural behavior; Structural models; Bouc–Wen model; Response history analysis; Model reduction; Seismic demand; Hysteresis
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2018.07.083

•A new inelastic model condensation (IMC) procedure that retains modal properties and hysteretic behavior.•Demonstration of the simplicity, accuracy, and efficiency of the IMC approach.•The IMC procedure can alleviate the computational burden of performance-based earthquake engineering. Computationally-efficient simulations of structural responses, such as displacements and inter-story drift ratios, are central to performance-based earthquake engineering. Calculating these responses involves potentially time-consuming response history analysis of inelastic structural behavior. To overcome this burden, this paper introduces a new inelastic model condensation (IMC) procedure. The method presented here is non-iterative and uses the modal properties of the full model (in the elastic range) to condense the structural model such that the condensed elastic model preserves the modal properties of the full model at certain modes specified by the analyst. Then, by replacing the inter-story elastic forces with hysteretic forces, the inelastic behavior of the full finite element model is incorporated into the condensed model. The parameters of these hysteretic forces are easily tuned, in order to fit the inelastic behavior of the condensed structure to that of the full model under a variety of simple loading scenarios. The fidelity of structural models condensed in this way is demonstrated via simulation for different ground motion intensities on three different building structures with various heights. The simplicity, accuracy, and efficiency of this approach could significantly alleviate the computational burden of performance-based earthquake engineering.