IJE TRANSACTIONS C: Aspects Vol. 31, No. 12 (December 2018) 1833-1839   

downloaded Downloaded: 0   viewed Viewed: 212

C. K. Yern, Fadzli M. Mohamed Nazri, M. Miari and M. Kassem
( Received: June 12, 2018 – Accepted: October 26, 2018 )

Abstract    Soft storey building is popular due to the functional and aesthetic purpose, despite its weakness in resisting seismic excitation. Nonlinear Static (Pushover) Analysis (POA) is a time saving and simple assessment procedure in Eurocode 8 (EC8). However, its reliability in designing structure remains a question. It is the same for fragility curve produced by using SPO2FRAG through POA. In this study, seismic performance of building using POA in EC8 is assessed. Empirical accuracy of fragility curve generated by POA (using SPO2FRAG) is studied and verified by Incremental Dynamic Analysis (IDA). Four models of regular and soft storey frame of 5- and 11-storey varying height were designed according to Eurocode 2 (EC2) and EC8. SAP2000 software was used to carry out POA. Capacity curve obtained is served as main input in SPO2FRAG software to generate fragility curve. Then, IDA is performed to generate IDA curves and fragility curves. Peak ground acceleration, PGA was converted into corresponding Sa(T1) using design spectrum from EC8. Performance levels of Life Safety (LS) and Near Collapse (NC) proposed by Vision-2000 are the main interest in this study. Results shown that the base shear resistance designed by using Lateral Force Method in EC8 is adequate.. Fragility curve generated by SPO2FRAG, indicated that regular 5-storey frame can capture the trend of fragility curve of IDA, but some deviation is observed for soft storey structure (5-storey). All 11-storey frames shown unsatisfactory match of fragility curve from what was generated by SPO2FRAG, compared to IDA.


Keywords    Pushover analysis, SPO2FRAG, Soft storey structure, Fragility curve, Eurocode, Performance level


References    1.   Kalkan, E. and Kunnath, S.K., "Adaptive modal combination procedure for nonlinear static analysis of building structures", Journal of Structural Engineering,  Vol. 132, No. 11, (2006), 1721-1731. 2.     Li, S., Zuo, Z., Zhai, C. and Xie, L., "Comparison of static pushover and dynamic analyses using RC building shaking table experiment", Engineering Structures,  Vol. 136, (2017), 430-440. 3.     Belejo, A. and Bento, R., "Improved modal pushover analysis in seismic assessment of asymmetric plan buildings under the influence of one and two horizontal components of ground motions", Soil Dynamics and Earthquake Engineering,  Vol. 87, (2016), 1-15. 4.     Soleimani, S., Aziminejad, A. and Moghadam, A.S., "Extending the concept of energy-based pushover analysis to assess seismic demands of asymmetric-plan buildings", Soil Dynamics and Earthquake Engineering,  Vol. 93, (2017), 29-41. 5.     Vamvatsikos, D. and Cornell, C.A., "Direct estimation of seismic demand and capacity of multidegree-of-freedom systems through incremental dynamic analysis of single degree of freedom approximation1", Journal of Structural Engineering,  Vol. 131, No. 4, (2005), 589-599. 6.     Baltzopoulos, G., Baraschino, R., Iervolino, I. and Vamvatsikos, D., "SPO2FRAG: Software for seismic fragility assessment based on static pushover", Bulletin of Earthquake Engineering,  Vol. 15, No. 10, (2017), 4399-4425. 7.     Patil, P. and Patil, V., "Development of fragility curves for seismic vulnerability of asymmetric RC buildings resting on sloping ground", Development,  Vol. 5, No. 01, (2018). 8.     Vision-2000, "Conceptual framework for performance based seismic engineering of buildings, Structural Engineers Association of California (SEAOC),  (1995). 9.     ATC-40, "Seismic evaluation and retrofit of concrete buildings", Applied Technology Council, report ATC-40. Redwood City, (1996). 10.   FEMA-273, "NEHRP guidelines for the seismic rehabilitation of buildings, Federal Emegency Management Agency,  (1997). 11.   FEMA-356, "Prestandard and commentary for the seismic rehabilitation of buildings, Federal Emegency Management Agency,  (2000). 12.   Freeman, S.A., "The capacity spectrum method", in Proceedings of the 11th European conference on earthquake engineering, Paris. (1998). 13.   Rossetto, T., Gehl, P., Minas, S., Galasso, C., Duffour, P., Douglas, J. and Cook, O., "FRACAS: A capacity spectrum approach for seismic fragility assessment including record-to-record variability", Engineering Structures,  Vol. 125, (2016), 337-348. 14.   Menasria, Y., Nouaouriaa, M. and Brahimi, M., "Probabilistic approach to the seismic vulnerability of RC frame structures by the development of analytical fragility curves", International Journal of Engineering-Transactions A: Basics,  Vol. 30, No. 7, (2017), 945-954. 15.   Jalayer, F. and Cornell, C.A., "A technical framework for probability-based demand and capacity factor (DCFD) seismic formats.” rms", (2003). 16.   Ibrahim, Y.E. and El-Shami, M.M., "Seismic fragility curves for mid-rise reinforced concrete frames in kingdom of saudi arabia", The IES Journal Part A: Civil & Structural Engineering,  Vol. 4, No. 4, (2011), 213-223. 17.   Vamvatsikos, D. and Cornell, C.A., "Incremental dynamic analysis", Earthquake Engineering & Structural Dynamics,  Vol. 31, No. 3, (2002), 491-514. 18.   Guevara-Perez, L.T., "“Soft story” and “weak story” in earthquake resistant design: A multidisciplinary approach", in Proceedings of 15th World Conference on Earthquake Engineering. (2012), 24-28. 19.   Nazri, F.M., Ghuan, T.C., Hussin, S.N. and Majid, T.A., "Evaluation of soil flexibility of the reclaimed area in penang using the non-destructive method", Natural Hazards,  Vol. 78, No. 2, (2015), 1267-1291.

International Journal of Engineering
E-mail: office@ije.ir
Web Site: http://www.ije.ir