ارزیابی رفتار لرزه‌ای قاب‌های فولادی مقید شده با مهاربندهای کمانش تاب هسته مرکب

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی عمران، دانشگاه کاشان، کاشان، ایران

چکیده

قاب مهاربندی کمانش تاب نوع ویژهای از قابهای فولادی مهاربندی هم‌محور است که در آن مهاربندها در برابر فشار کمانش نمی‌کنند و در نتیجه اتالف انرژی مطلوبی از خود نشان می‌دهد. لیکن هنگام وقوع زلزله‌های بزرگ، سختی پایین این مهاربندها بعد از تسلیم سبب تغییرمکان‌های دائمی بزرگ در قاب می‌شود. هدف تحقیق حاضر، ارزیابی رفتار لرزهای یک سیستم نوین سازهای موسوم به قاب فولادی مقید شده با مهاربندهای کمانش تاب هسته مرکب و مقایسه آن با رفتار قاب مهاربندی کمانش تاب متداول می‌باشد. بدین منظور، از سه روش تحلیل استاتیکی غیرخطی، تحلیل تاریخچه زمانی غیرخطی و تحلیل دینامیکی افزایشی روی انواع مدل‌های قاب مهاربندی کمانش تاب متداول و مرکب دارای طبقات مختلف استفاده می‌شود. مقادیر متوسط ضریب رفتار در قاب‌های فولادی مقید شده با مهاربند کمانش تاب مرکب برای روش‌‌های طراحی حالت حد نهایی و تنش مجاز به ترتیب برابر 10/2 و 14/7 به دست می‌آید. برای انجام تحلیل‌های تاریخچه زمانی، هفت زوج شتاب نگاشت از زلزله‌های گذشته در سطوح خطر مختلف مورد استفاده قرار می‌گیرد. نتایج تحلیل‌ها حاکی از این است که قاب‌های فولادی مرکب از بهبود عملکرد قابل توجهی در ضریب رفتار و نیز کاهش چشمگیر در مقدار جابه‌جایی پسماند بام نسبت به قاب‌های مهاربندی کمانش تاب متداول برخوردار هستند. به عالوه، با توجه به ارتفاع قاب و شدت زلزله، تغییر مکان جانبی نسبی درون طبقه در قاب‌های مرکب می‌تواند کاهش قابل ملاحظه‌ای داشته باشد

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Evaluation of Seismic Behavior of Steel Frames Constrained with Hybrid Core Buckling-restrained Braces

نویسندگان [English]

  • Mehdi Alborzi Verki
  • Hossein Tahghighi
Civil engineering department, University of Kashan, Kashan, Iran
چکیده [English]

Bucking restrained braced frame (BRBF) is a special type of concentrically braced frames that the braces do not buckle in compression. As a result, it shows a desirable energy dissipation behavior. However, low post-yield stiffness of these braces causes large residual deformations at high levels of earthquake intensities. The aim of this article was evaluation of the seismic behavior of a new steel structural system known as hybrid buckling-restrained braced frame (HBRBF). Nonlinear static analysis, nonlinear time history analysis and nonlinear incremental dynamic analysis (IDA) methods were used for standard and hybrid core BRBFs with different stories. The average values of seismic behavior factor (R) for HBRBFs were obtained 10.2 and 14.7 for ultimate limit state and allowable stress design methods, respectively. In order to carry out response history analyses, past earthquakes records were used with different hazard levels. Hybrid buckling-restrained braced frames were shown to have a significant improvement over standard BRBFs in terms of behavior factor and damage measures including inter-story drift ratios and residual displacements.

کلیدواژه‌ها [English]

  • Hybrid Buckling-restrained Brace
  • behavior factor
  • residual displacement
  • Nonlinear Analysis
[1]  W.A. López, R. Sabelli, Seismic Design of Buckling- Restrained Braced Frames, Steel tips, (2004) 78.
[2]  S. Kiggins, C.-M. Uang,  Reducing  Residual  Drift  of Buckling-Restrained Braced Frames as a Dual System, Engineering Structures, 28(11) (2006) 1525- 1532.
[3]  R. Sabelli, S. Mahin, C. Chang, Seismic Demands   on Steel Braced Frame Buildings with Buckling- Restrained Braces, Engineering Structures, 25(5) (2003) 655-666.
[4]  G.M.D. Gobbo, M.S. Williams, A. Blakeborough, Seismic performance assessment of Eurocode 8-compliant concentric braced frame buildings using FEMA P-58, Engineering Structures, 155 (2018), 192- 208.
[5]  C.   Ariyaratana,   L.A.   Fahnestock,    Evaluation    of Buckling-Restrained Brace Frame Seismic Performance Considering Reserve Strength, Eng Struct 33 (2011) 77–89.
[6]  D.J. Miller, L.A. Fahnestock, M.R. Eatherton, Development   and   Experimental    Validation    of  a Nickel–Titanium Shape Memory Alloy Self- Centering Buckling-Restrained Brace., Eng Struct 40 (2012) 288–298.
[7]  R. Tremblay, M. Lacerte, C. Christopoulos, Seismic Response of Multistory Buildings with Self-Centering Energy Dissipative Steel Braces. , Journal of Structural Engineering 134(1) (2008) 108–120.
[8]  C.M. Uang, M. Bruneau,  State-of-the-Art  Review  on Seismic Design of Steel Structures, Journal of Structural Engineering, 144 (2018), 03118002.
[9]  M. Nakashima, S. Iwai, M. Iwata, T. Takeuchi, S. Konomi, T. Akazawa, K. Saburi, Energy Dissipation Behaviour of Shear Panels Made of Low Yield Steel, Earthquake engineering & structural dynamics, 23(12) (1994) 1299-1313.
[10]  M. Sugisawa, H. Nakamura, Y. Ichikawa, M. Hokari, E. Saeki, R. Hirabayashi, M. Ueki, Development  of Earthquake-Resistant, Vibration Control, and Base Isolation Technology For Building Structures, Nippon Steel Technical Report, 66 (1996) 37–46.
[11]  C.C. Chen, S.Y. Chen, J.J. Liaw, Application of Low Yield Strength Steel on Controlled Plastification Ductile Concentrically Braced Frames, Can J Civ Eng 28 (2011) 823–836.
[12]  J.A. Jarrett, J.P. Judd, F.A. Charney, Comparative evaluation of innovative and traditional seismic- resisting systems using the FEMA P-58 procedure, Journal of Constructional Steel Research, 105 (2015), 107-118.
[13]  O. Atlayan, Hybrid Steel Frames, Ph.D. Dissertation, Virginia Tech, Blacksburg, 2013.
[14]  O. Atlayan, F.A. Charney, Hybrid buckling- restrained braced frames, Journal of Constructional Steel Research, 96 (2014) 95-105.
[15]  OpenSees, Open System for Earthquake Engineering Simulation, Pacific Earthquake Engineering Research Center, University of California, Berkeley, California, 2016.
[16]  I.R.o.I. Vice Presidency for Strategic Planning and Supervision, Instruction for Seismic Rehabilitation of Existing Buildings, Code No. 360 (1st Revision), 2014 (in Persian).
[17]  SEAOC, Recommended Provision for Buckling- restrained Braced Frames, (2001).
[18]  BHRC., Iranian Code of Practice for Seismic Resistant Design of Buildings: Standard No. 2800 (4th Revision), In persian, Building and Housing Research Center, Iran, 2014 (in Persian).
[19]  F. Mazzolani, V. Piluso, Theory and design of seismic resistant steel frames, CRC Press, 1996.
[20]  B. Asgarian, H. Shokrgozar, BRBF Response Modification Factor, Journal of constructional steel research, 65(2) (2009) 290-298.
[21]  C.M. Uang, Establishing R (or Rw) and Cd factors for building seismic provisions, Journal of Structural Engineering, 117(1) (1991) 19-28.
[22]  B. Schmidt, F. Bartlett, Review of resistance factor for steel: resistance distributions and resistance factor calibration, Canadian Journal of Civil Engineering, 29(1) (2002) 109-118.
[23]  M. Bruneau, C.M. Uang, R.  Sabelli,  Ductile  Design of Steel Structures, 2nd Ed., McGraw-Hill Professional, New York, 2011.
[24]  P.C. Lin, K.C. Tsai, K.J. Wang, Y.J. Yu, C.Y. Wei, A.C. Wu, C.Y. Tsai, C.H. Lin, J.C. Chen, A.H. Schellenberg, S.A. Mahin, C.W. Roeder, Seismic design and hybrid tests of a full-scale three-story buckling-restrained braced frame using welded end connections and thin profile, Earthquake Engineering and Structural Dynamics, 41 (2012) 1001–1020.
[25]  MHUD, Iranian National Building Code for Structural Loadings (part 6) ,3rd Revision, Ministry of Housing and Urban Development, Tehran, Iran, 2013 (in Persian).
[26]  MHUD, Iranian national building code (part 10): steel structure design, 4th Revision, Ministry of Housing and Urban Development, Tehran,  Iran,  2013 (in Persian).
[27]  FEMA, Quantification of building seismic performance   factors   (FEMA   P-695),   Prepared by Applied Technology Council for the Federal Emergency Management Agency, Washington D.C., 2009.
[28]  PEER Ground Motion Database, Pacific Earthquake Engineering Research Center, 2015.
[29]  H. Tahghighi,  Simulation  of  strong  ground  motion using the stochastic  method:  Application  and validation for near-fault region, Journal of Earthquake Engineering, 16 (2012), 1230-1247.
[30]  A. Systani, B. Asgarian, A. Jalaeefar, Incremental Dynamic Analysis of Concentrically Braced Frames (Cbfs) Under Near Field Ground Motions, Modares Civil Engineering Journal, 16, (2016) 135-145 (in Persian).
[31]  D. Vamvatsikos, C.A. Cornell, Seismic Performance, Capacity and Rellability of Structures as Seen Through Incremental Dynamic Analysis, in: Report No.151 (Ed.), Department of Civil and environmental Engineering, Stanford University, 2005.