Optimization of linear seismic isolation parameters via crow search algorithm

Abstract

In this study, isolation parameters of a seismic isolated structure were optimized via crow search algorithm (CSA). A shear frame model was generated with a base isolation system. The aim is to obtain isolation system parameters that result the minimum roof acceleration without exceeding the isolator displacement limits. The Matlab program was used for optimization operations and the SAP2000 program was used for structural analysis. The open application-programming interface (OAPI) was employed for the two programs to work together. Time history analyses were conducted using recorded near- and far-fault earthquake ground motions. Within the content of the study, linear isolator system parameters, which are the isolator period and damping ratio, were optimized through the linear time history analyses results by achieving the predefined aim. The analyses were performed for various isolation displacement limits and damping ratio ranges. The optimum results were determined at the range of various displacement limits and damping ratios by attaining the specified upper limits for displacement in all cases. Since higher damping ratios cause increased floor accelerations, optimum isolation parameters were achieved generally at the intermediate damping ratios well below the upper limits. Therefore, optimum isolation parameters are crucial for obtaining minimum floor accelerations. The verification of the optimum isolator parameters, which are achieved by the crow search algorithm employed, was made by comparing them with the results of a previous study.

Keywords

• Seismic isolation,Optimization,Crow search algorithm,Metaheuristic algorithm,SAP2000 OAPI

Doğrusal sismik izolasyon parametrelerinin karga arama algoritması ile optimizasyonu

Öz

Bu çalışmada, karga arama algoritması (CSA) kullanılarak sismik izolatörlü bir yapının izolasyon parametrelerinin optimizasyonu yapılmıştır. Bir kayma çerçevesi modeli ele alınarak tabanına izolasyon sistemi yerleştirilmiştir. Amaç, izolatör deplasman limitlerinin aşılmadan en düşük tepe ivmesini veren izolasyon sisteminin belirlenmesidir. Optimizasyon işlemleri için Matlab programı, yapısal analiz için ise SAP2000 programı kullanılmıştır. İki programın ortak çalışması için açık uygulama-programlama arayüzünden (OAPI) yararlanılmıştır. Yapısal analizler zaman tanım alanında yakın ve uzak saha etkilerine sahip gerçek deprem kayıtları kullanılarak yapılmıştır. Çalışma kapsamında ele alınan sismik izolatörlü yapının gerçekleştirilen doğrusal analizleri sonucunda izolatör deplasmanları sınırlandırılarak optimum izolatör periyodu ve sönüm oranı belirlenmiştir. Analizler farklı izolatör deplasman limitleri ve sönüm oranı aralıkları için yapılmıştır. Farklı deplasman limitleri ve sönüm oranı aralıklarında belirlenen optimum sonuçlar, deplasman üst limitine ulaşılarak elde edilmiştir. Yüksek sönüm oranının kat ivmelerinde artışa neden olması nedeniyle optimum izolasyon parametreleri genellikle en büyük sönüm oranı değerinde bulunmamıştır. Dolayısıyla, en düşük kat ivme değerlerinin elde edilmesi için optimum izolasyon sistem parametrelerinin belirlenmesi gerekmektedir. Kullanılan karga arama algoritması ile elde edilen optimum izolatör parametreleri benzer bir çalışmanın sonuçları ile kıyaslanarak geçerlilikleri ortaya konmuştur.

Anahtar Kelimeler

• Sismik izolasyon,Optimizasyon,Karga arama algoritması,Yarı-Sezgisel algoritma,SAP2000 OAPI

References

1. Alhan C, Sahin F. “Protecting vibration-sensitive contents: an investigation of floor accelerations in seismically isolated buildings”. Bulletin of Earthquake Engineering, 9, 1203-1226, 2001.
2. Naeim F, Kelly JM. Design of Seismic Isolated Structures: from Theory to Practice, 1nd ed. New York, USA, John Wiley & Sons, 1999.
3. Skinner RI, Robinson WH, McVerry GH. “Seismic isolation in New Zealand”. Nuclear Engineering and Design, 127(3), 281-289, 1991.
4. Hameed A, Koo MS, Do TD, Jeong JH. “Effect of lead rubber bearing characteristics on the response of seismic-ısolated bridges”. KSCE Journal of Civil Engineering, 12(3), 187-196, 2008.
5. Jangid RS. “Optimum lead-rubber ısolation bearings for near-fault motions”. Engineering Structures, 29(10), 2503-2513, 2007.
6. Eltahawy W, Ryan KL, Cesmeci S, Gordaninejad F. “Parameters affecting dynamics of three-dimensional seismic isolation”. Journal of Earthquake Engineering, 1-26, 2018 (Baskıda).
7. Wang Q, Fang H, Zou XK. “Application of Micro-GA for optimal cost base isolation design of bridges subject to transient earthquake loads”. Structural and Multidisciplinary Optimization, 41(5), 765-777, 2010.
8. Nigdeli SM, Bekdaş G, Alhan C. “Optimization of seismic isolation systems via harmony search”. Engineering Optimization, 46(11), 1553-1569, 2014.

9. Providakis CP. “Effect of LRB isolators and supplemental viscous dampers on seismic isolated buildings under near-fault excitations”. Engineering Structures, 30(5), 1187-1198, 2008.
10. Kelly JM. “The role of damping in seismic isolation”. Earthquake Engineering & Structural Dynamics, 28(1), 3-20, 1997.
11. Huang PC, Wan S, Yen JY. “A novel method of searching appropriate ranges of base isolation design parameters through entropy-based classification”. Structural Control and Health Monitoring, 16(4), 385-405, 2009.
12. Zou XK. “Integrated design optimization of base-isolated concrete buildings under spectrum loading”. Structural and Multidisciplinary Optimization, 36(5), 493-507, 2008.
13. Yucel M, Öncü-Davas S, Nigdeli SM, Bekdas G, Sevgen S. “Estimating of analysis results for structures with linear base isolation systems using artificial neural network model”. International Journal of Control Systems and Robotics, 3, 50-56, 2018.
14. Fan J, Long X, Zhang Y. "Optimum design of lead-rubber bearing system with uncertainty parameters”. Structural Engineering and Mechanics, 56(6), 959-982, 2015.
15. Pourzeynali S, Zarif M. “Multi-objective optimization of seismically isolated high-rise building structures using genetic algorithms”. Journal of Sound and Vibration, 311(3), 1141-1160, 2008.
16. Fallah N, Zamiri G, “Multi-objective optimal design of sliding base isolation using genetic algorithm”. Scientia Iranica A, 20(1), 87-96, 2013.
17. Charmpis DC, Komodromos P, Phocas MC, “Optimized earthquake response of multi-storey buildings with seismic isolation at various elevations”. Earthquake Engng Struct. Dyn. 41(15), 2289-2310, 2014.
18. Mojolic C, Hulea H, Parv BR. “Automatic design optimization tool for passive structural control systems”. AIP Conference Proceedings, 1863, 560036, 2017.
19. Barakat SA, AlHamaydeh MH, Nassif OM. “Optimization of seismic isolation systems with viscous fluid dampers using genetic algorithms”. 5th InternationalConference on Computational Methods in Structural Dynamics and Earthquake Engineering, Crete Island, Greece, 25-27 May 2015.
20. Moeindarbari, H, Taghikhany T. “Novel procedure for reliability‐based cost optimization of seismically isolated structures for the protection of critical equipment: A case study using single curved surface sliders”. Structural Control and Health Monitoring, 25(1), 1-19, 2018.
21. Chopra, AK. Dynamics of Structures: Theory and Applications to Earthquake Engineering, 2nd ed. Hall, NJ, Pearson Education, 2001.
22. Askarzadeh A. “A novel metaheuristic method for solving constrained engineering optimization problems: crow search algorithm”. Computers & Structures, 169, 1-12, 2016.
23. Sayed GI, Hassanien AE, Azar AT “Feature selection via a novel chaotic crow search algorithm”. Neural computing and applications, 31(1), 171-188, 2017.
24. Rizk-Allah RM, Hassanien AE, Bhattacharyya S. “Chaotic crow search algorithm for fractional optimization problems”. Applied Soft Computing, 71, 1161-1175, 2018b.
25. Mohit J, Asha R, Vijander S. “An improved crow search algorithm for high-dimensional problems”. Journal of Intelligent & Fuzzy Systems, 33(6), 3597-3614, 2017.
26. Turgut OE. “Crow search based multi-objective optimization of irreversible air refrigerators”. International Journal of Intelligent Systems and Applications in Engineering, 6(2), 103-112, 2018.
27. Tamilarasan A, Renugambal A, Manikanta D, Reddy GS, Sravankumar K, Sreekar B, Prasadreddy GV. “Application of crow search algorithm for the optimization of abrasive water jet cutting process parameters”. IOP Conference Series: Materials Science and Engineering, 390(1), 12-34, 2018.
28. Jamshidi M, Askarzadeh A. “Techno-economic analysis and size optimization of an off-grid hybrid photovoltaic, fuel cell and diesel generator system”. Sustainable Cities and Society, 44, 310-320, 2019.
29. MathWorks MATLAB. “The language of technical computing”. Version: R2015a. MathWorks, Natick, Massachusets, 2015.
30. SAP2000. “Structural analysis program: Static and dynamic finite element analysis of structures”. Version: 19. Computer and Structures. Berkeley, CA. 2018.
31. Pacific Earthquake Engineering Research Center. “PEER Strong Motion Database”. http://peer.berkeley.edu/smcat, (20.08.2018).
32. Pan P, Zamfirescu D, Nakashima M, Nakayasu N, Kashiwa H. “Base-isolation design practice in Japan: Introduction to the Post-Kobe approach”. Journal of Earthquake Engineering, 9(1), 147-171, 2005.