مطالعه‌ای بر مشخصات فیوزهای پیرامونی استفاده شده در ساختمان‌های تعمیرپذیر فلزی با حرکت الاکلنگی

نوع مقاله : Articles

نویسندگان

1 گروه مهندسی سازه، دانشگاه آزاد اسلامی واحد علوم و تحقیقات، تهران، ایران

2 پژوهشکده مهندسی سازه، پژوهشگاه بین‌المللی زلزله‌شناسی و مهندسی زلزله، تهران، ایران

چکیده

از فیوزهای سازه­ای و سیستم الاکلنگی جهت کاهش پاسخ ساختمان در مقابل زلزله و هدایت آسیب استفاده می­شود. در این سیستم ستون‌های ساختمان حذف شده و به‌جای آنها در مرکز از یک تکیه­گاه و در پیرامون ساختمان از فیوزهای سازه­ای غیرخطی استفاده می­شود. هدف اصلی از ایجاد این سیستم این است که هنگام زلزله اجزای سازه­ای به‌صورت الاستیک باقی مانده و تغییر شکل‌های غیرخطی در فیوز­های سازه­ای پیرامونی به وجود ­­آید که پس از زلزله می­توان در مدت‌زمان کوتاه و با هزینه کمتری نسبت به هزینه ساخت کل ساختمان، فیوزهای آسیب‌دیده را تعویض و از ساختمان بهره­برداری نمود. در این تحقیق مشخصات نوعی از فیوز سازه­ای مورد بررسی قرار گرفته و کاربرد آن در ساختمان با سیستم الاکلنگی تحت اثر زلزله حوزه نزدیک مورد مطالعه قرار می­گیرد. به‌طوری‌که حداکثر شتاب مطلق بام و برش پایه به‌طور چشمگیری کاهش می­یابد، اما میزان تغییر مکان جانبی نسبی طبقات در برخی از ساختمان‌ها افزایش یافته اما از حد مجاز کمتر است.

کلیدواژه‌ها


عنوان مقاله [English]

Study of Fuses Used in Steel Repairable Buildings with Seesaw Motion

نویسندگان [English]

  • Hossein Kazemifard 1
  • Mahmood Hosseini 2
  • Masoud Nekooei 1
  • Behrokh Hosseini Hashemi 2
1 Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 Structural Engineering Research Center, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran
چکیده [English]

Preventing the collapse of buildings during major earthquakes by using the capacity of plastic deformations of their structural members is regarded as the main philosophy behind most of the present seismic design codes. However, regarding large, especially near-source earthquakes, the amount of these plastic deformations may be so large that the building may lose its performance, and its demolishing may become inevitable. As a result, some adverse consequences are imposed to the stricken community. First, it is necessary to evacuate and shelter thousands, even hundreds of thousands of people who have lost their living or working spaces. Second, demolishing the severely damaged (but not collapsed) buildings is a very difficult and time consuming task since the considered ductility in design may not result in losing their integrity easily, and the common demolishing techniques may not be used for those buildings. Third, the debris removal of the demolished buildings, whose weight may be over millions of tons in case of large cities is very time consuming and costly. Finally, plenty of time and cost as well as a large number of skilled work forces are needed to construct the new buildings to replace the demolished ones.
Based on the above-mentioned issues, it is recommended to design and construct the buildings in such a way that they can be easily and quickly repaired with little cost, even after major earthquakes. Buildings that are created in this way can be called repairable or resilient buildings. Employing a structural system with seesaw motion is considered as one of the ways for creating earthquake-resilient buildings. In seesaw buildings, all circumferential columns at the lowest story are equipped with energy dissipating devices or structural fuses, all internal columns at that story are omitted, and a central mega hinge support with a grid of orthogonal strong girders are used to keep the integrity of the upper stories and transfer their gravity loads to the mega hinge support and the circumferential columns at the lowest story. In this research, the specifications of a kind of yielding-plates structural fuse, namely the initial stiffness and the yielding displacement, have been investigated and its application in a set of buildings with seesaw structural systems has been studied subjected to near-source earthquakes by performing a series of nonlinear time history analyses (NLTHA) using the scaled accelerograms of a set of selected earthquakes. Results of the conducted NLTHA indicate that the IO seismic performance level is mostly achieved in seesaw buildings by using the appropriate values for the aforementioned behavioral parameters of the structural fuses, while the conventional buildings with the same geometry mostly fail subjected to the same applied earthquakes. The maximum absolute acceleration of the buildings’ roofs and their base shear are significantly reduced by using the seesaw system; however, the roofs maximum displacements in some seesaw buildings are increased comparing to the conventional buildings, but they are still in the range of seismic design code limitations.

کلیدواژه‌ها [English]

  • Seesaw Motion
  • Structural Fuses
  • Nonlinear Time History Analysis
  • Seismic Vulnerability
  • Repairable Buildings
  1. Hosseini, M. and Ebrahimi, H. (2015) Proposing a yielding-plate energy dissipating connection for circumferential columns of steel rocking buildings and investigating its proper properties by nonlinear finite element analyses. 11th International Workshop on Advanced Smart Materials and Smart Structures Technology.
  2. Hosseini, M. and Alyasin, S. (1996) Deliberate directing of damage in lifeline systems subjected to earthquakes. Proceedings of the Hazard-96 Symposium, Toronto, Canada.
  3. Hosseini, M. and Ghorbani Amirabad, N. (2015) A structural fuse to create repairable buildings with seesaw motion in earthquake and its FE modeling. 11th Canadian Conference on Earthquake Engineering, Victoria, Canada.
  4. Fintel, M. and Ghosh, S. (1981) The structural fuse an inelastic approach to earthquake-resistant design of buildings. Civil Engineering ASCE, 51(1), 48-51.
  5. Goodfellow, R., Pinho, R., Salama, A., and Hancock, M. (1970) Applications of fuse inserts in seismic design of reinforced concrete structures. WIT Transactions on The Built Environment, 41.
  6. Vargas, R. and Bruneau, M. (2004) Seismic response of single degree of freedom structural fuse systems. 13th World Conference on Earthquake Engineering.
  7. Eatherton, M., Hajjar, J., Deierlein, G., Krawinkler, H., Billington, S., and Ma, X. (2008) Controlled rocking of steel-framed buildings with replaceable energy-dissipating fuses. Proceedings of the 14th World Conference on Earthquake Engineering.
  8. El-Bahey, S. and Bruneau, M. (2011) Buckling restrained braces as structural fuses for the seismic retrofit of reinforced concrete bridge bents. Engineering Structures, 33(3), 1052-1061.
  9. Clough, R.W. and Huckelbridge, A.A. (1977) Preliminary Experimental Study of Seismic Uplift of a Steel Frame. Earthquake Engineering Research Center, College of Engineering, University of California.
  10. Midorikawa, M., Azuhata, T., Ishihara, T. and Wada, A. (2006) Shaking table tests on seismic response of steel braced frames with column uplift. Earthquake Engineering & Structural Dynamics, 35(14), 1767-1785.
  11. Tremblay, R., Poirier, L.P., Bouaanani, N., Leclerc, M., Rene, V., Fronteddu, L. and Rivest, S. (2008) Innovative viscously damped rocking braced steel frames. Proceedings of the 14th World Conference on Earthquake Engineering, Beijing, China.
  12. Midorikawa, M., Ishihara, T., Azuhata, T., Hori, H., Kusakari, T., and Asari, T. (2009) Three-dimensional shaking table tests on seismic response of reduced-scale steel rocking frames. Proceedings of the 3rd International Conference on Advances in Experimental Structural Engineering.
  13. Hosseini, M. and Farsangi, E.N. (2012) Telescopic columns as a new base isolation system for vibration control of high-rise buildings. Earthquakes and Structures, 3(6), 853-867.
  14. Hosseini, M. and Bozorgzadeh, S. (2013) An innovative design for repairable regular steel buildings by using a 4-cell configuration structure with some inclined columns at base level, equipped with double-ADAS devices, and security cables at corners. Proceedings of the 13th East Asia-Pacific Conference on Structural Engineering and Construction (EASEC-13).
  15. Hosseini, M. and Kherad, S. (2013) A multi-stud energy dissipating device as the central fuse to be used in short-to mid-rise regular steel buildings with rocking motion. International Van Earthquake Symposium, Van, Turkey.
  16. Eatherton, M.R., Ma, X., Krawinkler, H., Mar, D., Billington, S., Hajjar, J.F., and Deierlein, G.G. (2014) Design concepts for controlled rocking of self-centering steel-braced frames. Journal of Structural Engineering, 140(11), 04014082.
  17. Hosseini, M., Fekri, M. and Yekrangnia, M. (2016) Seismic performance of an innovative structural system having seesaw motion and columns equipped with friction dampers at base level. The Structural Design of Tall and Special Buildings, 25(16), 842-865.
  18. Hosseini, M. and Alavi, S. (2014) A kind of repairable steel buildings for seismic regions based on buildings’ rocking motion and energy dissipation at base level. International Journal of Civil and Structural Engineering– IJCSE, 1(3).
  19. ASCE7-10 (2010) Minimum Design Loads for Buildings and Other Structures. American Society of Civil Engineers: Reston, VA.
  20. FEMA (2000) Pre-standard and Commentary for the Seismic Rehabilitation of Buildings (FEMA-356). Federal Emergency Management Agency (FEMA), Washington D.C.
  21. Commentary of Instruction for seismic Rehabilitation of Existing Buildings NO: 361 (2009) Office of Deputy for Strategic Supervision Bureau of Technical Execution System (in Persian).
  22. Iranian code of practice for seismic resistant design of buildings (2014) Standard No. 2800 (4th Edition): Iranian Building Codes and Standards (in Persian).