مطالعه آزمایشگاهی فیوز نوین کمانش‌ناپذیر کامپوزیتی برای مهاربندهای هم‌محور تحت بار چرخه‌ای

نوع مقاله : علمی - پژوهشی

نویسندگان

1 دانشجوی دکتری سازه، دانشگاه سمنان، سمنان، ایران

2 دانشیار، دانشگاه سمنان، سمنان، ایران

3 استاد، دانشگاه سمنان، سمنان، ایران

4 استاد، دانشگاه وسترن سیدنی، سیدنی، استرالیا

چکیده

مهاربندهای هم محور از متداول‌ترین عناصر قابل استفاده در تامین مقاومت جانبی سازه می‌باشند که به دلیل سختی زیاد، تغییر مکان جانبی کم، سهولت اجرا و مقرون به صرفه بودن همواره طراحان سازه‌های فولادی را به استفاده از این سیستم ترغیب نموده است. با این وجود از مهمترین معایب این نوع مهاربندها ضعف در شکل‌ّپذیری و کمانش اعضای مهاربند ضمن قرار گرفتن در معرض فشار، پیش از تسلیم شوندگی است. در سه دهه گذشته جهت رفع نقیصه‌های این سیستم پرکاربرد از تمهیداتی در اعضا مانند فیوزهای سازه‌ای استفاده شده است. این مقاله به ارائه یک فیوز نوین کمانش‌ناپذیر کامپوزیتی (CBRF) برای استفاده در اعضای مهاربند می‌پردازد. این فیوز با ابعادی به نسبت کوچک، تکامل یافته مهاربندهای کمانش‌ناپذیر طول کوتاه (RL-BRBs)، یک میراگر هیسترزیس با رفتار و ظرفیت باربری متفاوت در کشش و فشار است. استفاده از اجزای کششی مضاعف در این فیوز توانسته است تا کاهش ظرفیت کششی اعضای مهاربند ناشی از استفاده فیوز‌های معمول سازه‌ای در آن‌ها را مرتفع نماید. در این مطالعه تعدادی از پارامترهای مهم طراحی فیوز پیشنهادی مانند طول و ضخامت هسته مرکزی مورد بررسی قرار گرفته است. در ادامه طی یک مطالعه آزمایشگاهی دو نمونه از این قطعه طراحی، ساخته و در آزمایشگاه تحت بارگذاری چرخه‌ای مورد آزمایش قرار گرفته است. در انتها پارامتر‌های تنظیم کننده مقاومت ضمن بررسی ‌ نمودار هیسترزیس نمونه‌ها محاسبه و مقایسه شده است. نتایج حاکی از رفتار شکل‌پذیر فیوز پیشنهادی با کرنش متوسط ۵٪، توام با ظرفیت کششی و استهلاک انرژی مناسب می‌باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental Evaluation of an Innovative Buckling-Restrained Fuse for Concentrically Braced Frames under Cyclic Loading

نویسندگان [English]

  • Masoud Mohammadi 1
  • Mohammad Ali Kafi 2
  • Ali Kheyroddin 3
  • Hamid Reza Ronagh 4
1 Ph.D. Candidate, Dept. of Civil Engineering. Semnan University, Semnan, Iran
2 Associate Professor, Dept. of Civil Engineering, Semnan University, Semnan, Iran
3 Professor, Dept. of Civil Engineering, Semnan University, Semnan, Iran
4 Professor, Center for Infrastructure Engineering, Western Sydney University, Sydney, Australia
چکیده [English]

Concentrically braced frames (CBFs) have become prevalent as a lateral load resisting system due to their rigidity, low lateral displacement and ease of implementation over the last three decades. These advantages encourage the increasing utilization of this system in the construction industry. Despite the advantages of CBFs, the lack of ductility and buckling of the bracing element before yielding is the main disadvantage this lateral system. In the last three decades, studies have become focused on the ductility and energy dissipation of the CBFs that were modified in terms of using dampers and fuse segments. The current study aims to presents an innovative Composite Buckling Restrained Fuse (CBRF) to be used as a bracing segment. CBRF with relatively small dimensions is an improvement on Reduced Length Buckling Restrained Brace (RL-BRBs) as a hysteretic damper with different performance in tension and compression. Extra tensile elements in a novel configuration were used to compensate for the limitation of tensile strength that exists in bracing elements containing ordinary fuse segments. Here, some key design parameters of CBRF such as length and cross-sectional area of the core are discussed theoretically. Two specimens were designed and tested under cyclic loads. Moreover, the hysteretic response of the specimens was evaluated to calculate their strength adjustment parameters. The results indicate that the proposed CBRF has a ductile behavior with an average strain of 5% and high energy absorption capacity along with sufficient tensile strength.

کلیدواژه‌ها [English]

  • steel structure
  • Braced Frames
  • Structural Fuse
  • Ductility
  • Hysteretic damper
  • Buckling-restrained braces
[1] Craighead, G. (2009). Chapter 1 - High-Rise Building Definition, Development, and Use. in High-Rise Security and Fire Life Safety (Third Edition)Boston: Butterworth-Heinemann, pp. 1-26.
[2] EERI. (1995). Northridge Earthquake Reconnaissance Report. Vol. 1. Earthquake Spectra, vol. supplement C to vol. 11.
[3] Pall, A. S. and Marsh, C. (1982). Response Of Friction Damped Braced Frames. ASCE J Struct Div, Article vol. 108, no. ST6, pp. 1313-1323.
[4] Grigorian, C. E., Yang, T. S., and Popov, E. P. (1993). Slotted Bolted Connection Energy Dissipators. Earthquake Spectra, vol. 9, no. 3, pp. 491-504.
[5] Mualla, I. H. and Belev, B. (2002). Performance of steel frames with a new friction damper device under earthquake excitation. Engineering Structures, vol. 24, no. 3, pp. 365-371.
[6] Skinner, R. I., Kelly, J. M., and Heine, A. J. (1974). Hysteretic dampers for earthquake‐resistant structures. Earthquake Engineering & Structural Dynamics, vol. 3, no. 3, pp. 287-296.
[7] Skinner, R. I., Tyler, R. G., Heine, A. J., and Robinson, W. H. (1980). Hysteretic dampers for the protection of structures from earthquakes. Bulletin of the New Zealand national society for earthquake engineering, vol. 13, no. 1, pp. 22-36.
[8] TahamouliRoudsari, M., Eslamimanesh, M. B., Entezari, A. R., Noori, O., and Torkaman, M. (2018). Experimental Assessment of Retrofitting RC Moment Resisting Frames with ADAS and TADAS Yielding Dampers. Structures, vol. 14, pp. 75-87.
[9] Mahmoudi Sahebi, M. and Khanjani, F. (2017). Evaluation of seismic performance of X bracing systems equipped with flexural yielding dampers. Structural and construction engineering, vol. 4, no. 2, pp. 123-138.
[10] Bouwkamp, J., Vetr, M. G., and Ghamari, A. (2016). An analytical model for inelastic cyclic response of eccentrically braced frame with vertical shear link (V-EBF). Case Studies in Structural Engineering, vol. 6, pp. 31-44.
[11] Zahrai, S. M. and Arman Nikoo, S. (2015). Comparing Seismic Performance of Yielding Damped Braced Frames with Mild and Low-Yield Steel in Typical Steel Buildings. (in eng). Modares Civil Engineering journal, vol. 14, no. 4, pp. 39-52.
[12] Andalib, Z., Kafi, M. A., Kheyroddin, A., and Bazzaz, M. (2014). Experimental investigation of the ductility and performance of steel rings constructed from plates. Journal of Constructional Steel Research, vol. 103, pp. 77-88.
[13] Kafi, M. A. (2008). Laboratory examination and analysis of the impact of steel ring in concentric braces. Ph. D., Civil engineering, IRAN Univesity of science and technology, Tehran.
[14] Andalib, Z., Kafi, M. A., Kheyroddin, A., Bazzaz, M., and Momenzadeh, S. (2018). Numerical evaluation of ductility and energy absorption of steel rings constructed from plates. Engineering Structures, vol. 169, pp. 94-106.
[15] Bazzaz, M., Andalib, Z., Kafi, M. A., and Kheyroddin, A. (2015). Numerical Comparison of the Seismic Performance of Steel Rings in Off-centre Bracing System and Diagonal Bracing System. Steel and Composite Structures, vol. 19, pp. 917-937.
[16] Bazzaz, M., Andalib, Z., Kafi, M. A., and Kheyroddin, A. (2015). Evaluating the Performance of OBS-C-O in Steel Frames under Monotonic Load. Earthquakes and Structures, vol. 8, pp. 697-710.
[17] Bazzaz, M., Kheyroddin, A., Kafi, M. A., and Andalib, Z. (2012). Evaluation of the Seismic Performance of Off-Centre Bracing System with Ductile Element in Steel Frames. Steel and Composite Structures, vol. 12, pp. 445-464.
[18] Yoshino, T. and Karino, Y. (1971). Experimental study on shear wall with braces: Part 2. Summaries of technical papers of annual meeting. (in Japanese). Architectural Institute of Japan, Structural Engineering Section, vol. 11, pp. 403-404.
[19] Xie, Q. (2005). State of the art of buckling-restrained braces in Asia. Journal of Constructional Steel Research, vol. 61, no. 6, pp. 727-748.
[20] Sabelli, R. (2001). Research on improving the design and analysis of earthquake-resistant steel braced frames. NEHRP, California.
[21] López, W. A. and Sabelli, R. (2004). Seismic Design of Buckling-Restrained Braced Frames, Steel Tips. California.
[22] Tremblay, R., Bolduc, P., Neville, R., and DeVall, R. (2006). Seismic testing and performance of buckling restrained bracing systems. Canadian Journal of Civil Engineering, vol. 33, pp. 183-198.
[23] Mazzolani, F. M. (2008). Innovative metal systems for seismic upgrading of RC structures. (in English). Journal of Constructional Steel Research, Article vol. 64, no. 7-8, pp. 882-895.
[24] Mirtaheri, M., Gheidi, A., Zandi, A. P., Alanjari, P., and Samani, H. R. (2011). Experimental optimization studies on steel core lengths in buckling restrained braces. Journal of Constructional Steel Research, vol. 67, no. 8, pp. 1244-1253.
[25] Hoveidae, N., Tremblay, R., Rafezy, B., and Davaran, A. (2015). Numerical investigation of seismic behavior of short-core all-steel buckling restrained braces. Journal of Constructional Steel Research, vol. 114, pp. 89-99.
[26] Kachooee, A. and Kafi, M. A. (2018). A Suggested Method for Improving Post Buckling Behavior of Concentric Braces Based on Experimental and Numerical Studies. Structures, vol. 14, pp. 333-347.
[27] Fanaie, N. and Dizaj, E. (2014). Response modification factor of the frames braced with reduced yielding segment BRB. Structural Engineering and Mechanics, vol. 50, no. 1.
[28] Dizaj, E., Fanaie, N., and Zarifpour, A. (2017). Probabilistic seismic demand assessment of steel frames braced with reduced yielding segment buckling restrained braces. Advances in Structural Engineering, vol. 21, no. 7, pp. 1002-1020.
[29] Mohammadi, M., Kafi, M. A., Kheyroddin, A., and Ronagh, H. R. (2018). Experimental Study Of Innovative Composite Buckling-Restrained Fuse For Concentrically Braced Frames Under Cyclic Load, presented at the ASEA SEC 04, Brisbane, Australia.
[30] Mohammadi, M., Kafi, M. A., Kheyroddin, A., and Ronagh, H. R. (2018). Experimental And Numerical Investigation Of Innovative Composite Buckling-Restrained Fuse, presented at the ACMSM25, Brisbane, Australia.
[31] Pandikkadavath, M. S. and Sahoo, D. R. (2016). Cyclic testing of short-length buckling-restrained braces with detachable casings. Earthquakes and Structures. vol. 10, pp. 699-716.
[32] Sahoo, D. R. and Pandikkadavath, M. S. (2014). Experimental Study on Reduced-length Buckling-restrained Braces under Slow-cyclic Loading, presented at the Tenth U.S. National Conference on Earthquake Engineering, Anchorage, Alaska.
[33] Bruneau, M., Uang, C. M., and Sabelli, R. (2011). Ductile Design of Steel Structures, 2nd Edition. McGraw-Hill Education.
[34] Budynas, R. G., Nisbett, J. K., and Shigley, J. E. (2011). Shigley's mechanical engineering design. 9th Ed. New York: McGraw-Hill.
[35] Usami, T., Wang, C., and Funayama, J. (2011). Low-Cycle Fatigue Tests of a Type of Buckling Restrained Braces. Procedia Engineering, vol. 14, pp. 956-964.
[36] DIN 17100, Steels for general structural purposes-Quality Standard. (1980).
[37] ASTM E8/E8M-16a, Standard Test Methods for Tension Testing of Metallic Materials. (2016).
[38] AISC341. (2016). ANSI/AISC 341-16, Seismic Provisions for Structural Steel Buildings. United States of America, Chicago: American Institute of Steel Construction.
[39] ATC24. (1992). Guidelines for cyclic seismic testing of components of steel structures. Redwood City, Calif.: Applied Technology Council.
[40] Uriz, P. (2008). Toward earthquake-resistant design of concentrically braced steel-frame structures. Berkeley, Calif.: Pacific Earthquake Engineering Research Center.