Estimating the response of concrete moment frames subjected to individual ground motions using endurance time excitation functions fitted to average acceleration response spectra

Document Type : Article

Authors

Department of Civil Engineering, Sharif University of Technology, Tehran, Iran

Abstract

Endurance Time (ET) method is a time history-based analysis procedure that applies special intensifying acceleration functions for estimating the seismic performance of structures at different excitation levels in every single analysis, and therefore, remarkably reduces the computational time, effort, and cost. For some structures with complicated models, such as dams, performing multiple seismic analyses are impractical. In such cases, it is recommended that researchers pay conscious attention to choose appropriate and compatible Endurance Time excitation functions (ETEF) considering the basic properties of their structure. However, in this study, it is observed that selecting and using various ETEFs for analyzing an intermediate concrete moment frame structure subjected to individual earthquake ground motions will lead us to obtain false and unreliable responses. In other words, different ETEF series have significantly different accuracies (over 26 percent error) in predicting the responses of the mentioned structure subjected to individual earthquake ground motions. This problem mainly arises due to the turbulent nature of the spectrum of a single ground motion which is in contrast to the smoothed shape of spectra of the ETEFs. One solution to avoid this problem might be to produce a specific ETEF.

Keywords


References

[1]        Valamanesh, V., Estekanchi, H.E., and Vafai, A., “Characteristics of second-generation endurance time acceleration functions”, Scientia Iranica, Transaction A, Civil Engineering, 17(1), pp. 53-61 (2010).
[2]        Mashayekhi, M., Estekanchi, H.E., and Vafai, A., “Optimal objective function for simulating endurance time excitations”, Scientia Iranica, Transaction A, Civil Engineering, 27(4), pp. 1728-1739 (2020).
[3]        ASCE, “Minimum design loads and associated criteria for buildings and other structures, ASCE 7-10”, American Society of Civil Engineers (2010).
[4]        Building and Housing Research Center (BHRC), “Iranian code of practice for seismic resistant design of buildings, Standard No. 2800, 4th Ed.”, Tehran, Iran (2016).
[5]        Computers & Structures Inc (CSI), “CSI Analysis Reference Manual” (2019).
[6]       Federal Emergency Management Agency (FEMA), “Quantification of building seismic performance factors, FEMA P-695”, Washington, DC (2009).
[7]       Open System for Earthquake Engineering Simulation (OpenSees), “Pacific Earthquake Engineering Research Center”, Available at: http://peer.berkeley.edu (2021)
[8]        UFC, “Unified Facilities Criteria, UFC 3-301-01”, Department of defense, United States of America (2019).
[9]        Riahi, H.T. and Estekanchi, H.E., “Comparison of different methods for selection and scaling of ground motion time histories”, 5th International conference on seismology and earthquake engineering, pp. 13-16 (2007).
[10]       Shirkhani, A., Azar, B.F., and Basim, M.C., “Optimum slip load of T-shaped friction dampers in steel frames by endurance time method”, ‎Proceedings of the Institution of Civil Engineers - Structures and Buildings, 173(10), pp. 746-760 ‎‎(2020).
[11]       Shirkhani, A., Azar, B.F., Basim, M.C., et al., “Numerical Methods in Civil Engineering Performance-based optimal distribution of viscous dampers in structure using hysteretic energy compatible endurance time excitations”, Journal of Numerical ‎Methods in Civil Engineering, 5(3), pp. 46-55 (2021).
[12]        Vafai, A. and Estekanchi, H.E., “The Endurance Time Method: Research Highlights” (2016).
[13]       Basim, M., Estekanchi, H.E., and Vafai, A., “A methodology for value based seismic design of structures by the endurance time method”, Scientia Iranica, Transaction A, Civil Engineering, 23(6), pp. 2514-2527 (2016).
[14]       Bazmooneh, A. and Estekanchi, H.E., “Determination of target time for endurance time method at different seismic hazard levels”, Scientia Iranica, Transaction A, Civil Engineering, 25(1), pp. 33-49 (2018).
[15]      Mashayekhi, M. and Estekanchi, H.E., “Investigation of strong-motion duration consistency in Endurance Time excitation functions”, Scientia Iranica, Transaction A, Civil Engineering, 20(4), pp. 1085-1093 (2013).
[16]       Ahmadie Amiri, H., Pournamazian Najafabadi, E., Estekanchi, H.E., et al., “Performance-based seismic design and assessment of low-rise steel special moment resisting frames with block slit dampers using endurance time method”, Engineering Structures, 224(110955) (2020).
[17]       Estekanchi, H.E., Vafai, A., and Basim, M.C., “Design and assessment of seismic resilient structures by the endurance time method”, Scientia Iranica, Transaction A, Civil Engineering, 23(4), pp. 1648-1657 (2016).
[18]       Zhang, R., Zhang, L., Pan, C., et al., “Generating high spectral consistent endurance time excitations by a modified time-domain spectral matching method”, Soil Dynamics and Earthquake Engineering, 145(106708) (2021).
[19]       Salamon, J.W., Hariri Ardebili, M.A., Estekanchi, H.E., et al., “Seismic assessment of a dam-foundation-reservoir system using Endurance Time Analysis”, Sustainable and Safe Dams Around the World, pp. 2659-2669 (2019).