مصالح و سازه های بتنی

مصالح و سازه های بتنی

ارزیابی ضریب رفتار سازه‌های هیبریدی(بتنی-فولادی) نامنظم در ارتفاع

نوع مقاله : مقاله پژوهشی

نویسندگان
1 دانشجوی دکترای گروه عمران واحد شاهرود دانشگاه آزاد اسلامی شاهرود ایران
2 استادیار گروه مهندسی عمران واحد شاهرود، دانشگاه آزاد اسلامی
3 استادیار گروه عمران، واحد شاهرود دانشگاه آزاد اسلامی، شاهرود، ایران
چکیده
سازه‌های هیبریدی بتنی - فولادی با تلفیق مطلوب عملکرد دو مصالح، به ویژه در مناطق با خطر لرزه‌خیزی بالا کاربرد گسترده‌ای یافته‌اند. با این حال، تأثیر نامنظمی در ارتفاع بر پارامترهای کلیدی طراحی لرزه‌ای مانند ضریب رفتار (R) در این سازه‌ها به اندازه کافی مورد بررسی کمی قرار نگرفته است. این پژوهش به ارزیابی کمی ضریب رفتار در قاب‌های خمشی متداول که در آن‌ها سیستم باربر جانبی در ارتفاع از بتن مسلح به فولاد تغییر می‌کند، می‌پردازد. برای این منظور، مجموعه‌ای از مدل‌های ۶، ۱۲و ۱۸ طبقه با درجات مختلف نامنظمی مدل‌سازی و با تحلیل استاتیکی غیرخطی مورد ارزیابی قرار گرفتند. پس از استخراج منحنی‌های ظرفیت، پارامترهای ضریب رفتار (R)، ضریب اضافه مقاومت (Ω) و ضریب شکل‌پذیری (μ) با استفاده از روش‌های استاندارد دوخطی‌سازی محاسبه شده است. نتایج نشان می‌دهد که محل تغییر مصالح و شدت نامنظمی تأثیر مستقیم و قابل‌ملاحظه‌ای بر مقادیر این ضرایب دارد. مقایسه با مقادیر مرجع برای سازه‌های منظم حاکی از غیرمحافظه‌کارانه بودن استفاده از این مقادیر در طراحی سازه‌های هیبریدی نامنظم است. به‌طورکلی، عملکرد لرزه‌ای قاب‌های هیبریدی در تحمل بار جانبی، برتری قابل‌توجهی بین ۱۷ تا ۳۹ درصد در ضریب رفتارنسبت به قاب‌های تمام‌بتنی معادل ارائه می‌دهند. یافته‌های نهایی بر ضرورت محاسبه اختصاصی ضریب رفتار بر اساس الگو و شدت نامنظمی در این سازه‌ها تأکید دارد تا با اطمینان بیشتر، به تاب‌آوری بالاتر و طراحی اقتصادی‌تر در مناطق زلزله‌خیز دست یافت.
کلیدواژه‌ها
موضوعات

عنوان مقاله English

Evaluation of the Behavior Factor of Hybrid (Concrete-Steel) Vertically Irregular Structures

نویسندگان English

jalil khani 1
Aboozar Mirzakhani 2
hamed valizade 3
1 iau, shahrood, iran
2 Assistant professor, Department of Civil Engineering, Shahrood Branch, Islamic Azad University,
3 Assistant professor if iau
چکیده English

Hybrid reinforced concrete-steel structures, due to their optimal integration of the advantages of both materials, have found widespread application in the construction industry, particularly in regions with high seismic hazard. However, the quantitative impact of vertical irregularity on key seismic design parameters, such as the behavior factor (R), in these structures has not been sufficiently investigated. This study aims to quantitatively evaluate the behavior factor in ordinary moment-resisting frames where the lateral load-bearing system transitions from reinforced concrete to steel over the height. To this end, a series of 6-, 12-, and 18-story models with varying degrees of irregularity were modeled and assessed using nonlinear static (Pushover) analysis. Following the derivation of capacity curves, key parameters including the behavior factor (R), overstrength factor (Ω), and ductility factor (μ) were calculated employing standard bilinearization methods. The results indicate that the location of the material transition and the severity of irregularity have a direct and significant influence on the values of these factors. A comparison with code-specified values for regular structures reveals that using these values for the design of irregular hybrid structures may be non-conservative. In general, the seismic performance of hybrid frames in resisting lateral loads demonstrates a notable superiority, showing 17% to 39% higher behavior factors compared to their equivalent fully reinforced concrete counterparts. The final findings underscore the necessity of calculating the behavior factor on a case-specific basis, considering the pattern and degree of irregularity. This approach paves the way for achieving higher seismic resilience and more economical design of tall buildings in earthquake-prone zones.

کلیدواژه‌ها English

Hybrid reinforced concrete-steel structures
Vertical irregularity
Behavior factor (R)
Nonlinear static analysis (Pushover)
Moment resisting frame
[1] Askouni, P. K. (2023). The Behavior of Hybrid Reinforced Concrete-Steel Buildings under Sequential Ground Excitations. Computation, 11(2), 102.
[2] European Committee for Standardization. (2004). *Eurocode 2: Design of Concrete Structures—Part 1-1: General Rules and Rules for Buildings* (EN 1992-1-1). Brussels, Belgium.
[3] European Committee for Standardization. (2009). *Eurocode 3: Design of Steel Structures—Part 1-1: General Rules and Rules for Buildings* (EN 1993-1-1). Brussels, Belgium.
[4] European Committee for Standardization. (2004). Eurocode 8: Design of Structures for Earthquake Resistance—Part 1: General Rules, Seismic Actions and Rules for Buildings (EN 1998-1). Brussels, Belgium.
[5] European Committee for Standardization. (2004). Eurocode 8: Design of Structures for Earthquake Resistance—Part 3: Assessment and Retrofitting of Buildings (EN 1998-3). Brussels, Belgium.
[6] European Committee for Standardization. (2004). Eurocode 8: Design of Structures for Earthquake Resistance—Part 5: Foundations, Retaining Structures and Geotechnical Aspects (EN 1998-5). Brussels, Belgium.
[7] European Committee for Standardization. (2004). Eurocode 8: Design of Structures for Earthquake Resistance—Part 6: Towers, Masts and Chimneys (EN 1998-6). Brussels, Belgium.
[8] Askouni, P. K. (2025). Seismic Comparison of Hybrid Steel-Reinforced Concrete and Conventional Frames. Applied Sciences, 15(9), 3772.
[9] Maley, T. J., Sullivan, T. J., & Pampanin, S. (2012). Issues with the Seismic Design of Mixed MRF Systems. In Proceedings of the 15th World Conference on Earthquake Engineering, Lisbon, Portugal, 24-28 September.
[10] Fanaie, N., & Shamlou, S. O. (2015). Response Modification Factor of Mixed Structures. Steel and Composite Structures, 19(6), 1449-1466.
[11] Bhattarai, A., & Shakya, A. C. (2023). Response Reduction Factor of Steel–RC Hybrid Structure. KEC Journal of Science and Engineering, 7, 77-81.
[12] Kiani, A., Kheyroddin, A., Kafi, M. A., & Naderpour, H. (2022). Seismic Fragility Assessment for Mixed Concrete/Steel Buildings Considering the Appropriate Position of the Transition Story. Soil Dynamics and Earthquake Engineering, 163, 107552.
[13] Kiani, A., Kheyroddin, A., Kafi, M. A., & Naderpour, H. (2023). Nonlinear Study of the Method of Transition in Mixed Concrete/Steel Structures. Soil Dynamics and Earthquake Engineering, 170, 107925.
[14] Ghanbari, B., Fathi, M., & Akhaveissy, A. H. (2023). Fragility Curves for Reinforced Concrete (RC)/Steel Vertical Hybrid Frame Structure under Mainshock–Aftershock Sequences. Journal of Structural Integrity and Maintenance, 8(3), 179-187.
[15] Askouni, P. K., & Papagiannopoulos, G. A. (2021). Seismic Behavior of a Class of Mixed Reinforced Concrete-Steel Buildings Subjected to Near-Fault Motions. Infrastructures, 6(12), 172.
[16] Li, L., Li, G. Q., & Liu, Y. (2012). Simplified Algorithm of the Novel Steel-Concrete Mixed Structure under Lateral Load. *International Journal of High-Rise Buildings, 1*(3), 247-254.
[17] Kaveh, A., & Ardebili, S. R. (2023). Optimal Design of Mixed Structures under Time-history Loading Using Metaheuristic Algorithm. Periodica Polytechnica Civil Engineering, 67(1), 57-64.
[18] Kiani, A., Yang, T. Y., Kheyroddin, A., Kafi, M. A., & Naderpour, H. (2024). Quantification of Seismic Performance Factors of Mixed Concrete/Steel Buildings Using the FEMA P695 Methodology. Structures, 61, 106144.
[19] Pnevmatikos, N., Blachowski, B., & Papavasileiou, G. (2019). Damage Detection of Mixed Concrete/Steel Frame Subjected to Earthquake Excitation. In Proceedings of the 7th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2019), Crete, Greece, 24-26 June.
[20] Papagiannopoulos, G. (2024). On the Modal Damping Ratios of Mixed Reinforced Concrete–Steel Buildings. Soil Dynamics and Earthquake Engineering, 178, 108481.
[21] Farghaly, A. A. (2013). Parametric Study on Equivalent Damping Ratio of Different Composite Structural Building Systems. Steel and Composite Structures, 14(4), 349-365.
[22] Sivandi-Pour, A., Gerami, M., & Kheyroddin, A. (2015). Determination of Modal Damping Ratios for Non-classically Damped Rehabilitated Steel Structures. Iranian Journal of Science and Technology, Transactions of Civil Engineering, 39(C2), 81-92.
[23] Sivandi-Pour, A., Gerami, M., & Kheyroddin, A. (2016). Uniform Damping Ratio for Non-classically Damped Hybrid Steel Concrete Structures. International Journal of Civil Engineering, 14(1), 1-11.
[24] Sivandi-Pour, A., Gerami, M., & Khodayarnezhad, D. (2014). Equivalent Modal Damping Ratios for Non-classically Damped Hybrid Steel Concrete Buildings with Transitional Storey. Structural Engineering and Mechanics, 50(3), 383-401.
[25] Liu, W., Ni, Y. Q., Ikago, K., & Ao, W. K. (2023). Seismic Control of Base-Isolated Structures Using Rate-Independent Damping Devices. Journal of Building Engineering, 78, 107744.
[26] Liu, W., Ni, Y. Q., & Ao, W. K. (2024). Feasibility Study of a Novel Modal Decomposition Method for Low-Frequency Structure with Nonproportionally Distributed Rate-Independent Linear Damping. Structural Control and Health Monitoring, 2024, 8896925.
[27] Askouni, P. K. (2024). The Influence of Soil Deformability on the Seismic Response of 3D Mixed R/C–Steel Buildings. Infrastructures, 9(5), 80.
[28] Roy, A., Santra, A., & Roy, R. (2018). Estimating Seismic Response under Bi-directional Shaking per Uni-directional Analysis: Identification of Preferred Angle of Incidence. Soil Dynamics and Earthquake Engineering, 106, 163-181.
[29] Rigato, A. B., & Medina, R. A. (2007). Influence of Angle of Incidence on Seismic Demands for Inelastic Single-Storey Structures Subjected to Bi-directional Ground Motions. Engineering Structures, 29(10), 2593-2601.
[30] Di Sarno, L., Amiri, S., & Garakaninezhad, A. (2020). Effects of Incident Angles of Earthquake Sequences on Seismic Demands of Structures. Structures, 28, 1244-1251.
[31] Altunışık, A. C., & Kalkan, E. (2017). Earthquake Incidence Angle Influence on Seismic Performance of Reinforced Concrete Buildings. Sigma Journal of Engineering and Natural Sciences, 35(4), 609-631.
[32] Dwivedi, A., Reddy, K. K., & Somala, S. N. (2022). Study of Seismic Orientation of Structure with Bi-directional Response Analysis in the Vicinity of Branched Fault Earthquake Rupture. Structures, 37, 613-623.
[33] Larijani, A. K., & Tehrani, P. (2024). Investigating the Effect of Earthquake Incident Angle on Seismic Response and Fragility Analysis of Irregular RC Buildings with Nonparallel Systems. Structures, 38, 107135.
[34] Building and Housing Research Center (BHRC). (2015). Iranian Code of Practice for Seismic Resistant Design of Buildings: Standard No. 2800 (4th ed.). Tehran, Iran.
[35] Federal Emergency Management Agency (FEMA). (2000). Prestandard and Commentary for the Seismic Rehabilitation of Buildings (FEMA 356). Washington, D.C., USA.
[36] Hosseini Bay, S. M., & Gholamzadeh, M. (2017). Bilinearization of Pushover Curve and Determination of Behavior Factor Using Chopra's Method. In The 3rd Annual Conference on Architectural, Urban Planning and Urban Management Research, Shiraz, Iran.
[37] Uang, C. M. (1991). Establishing R (or Rw) and Cd Factors for Building Seismic Provisions. Journal of Structural Engineering, 117(1), 19-28.
[38] Institute of Standards and Industrial Research of Iran (ISIRI). (2015). Iranian National Standard ISIRI 3631: Rolled Steel Sections for Building Purposes – Specifications. Tehran, Iran.
[39] Karavasilis, T. L., Bazeos, N., & Beskos, D. (2008). Seismic Response of Plane Steel MRF with Setbacks: Estimation of Inelastic Deformation Demands. Journal of Constructional Steel Research, 64(6), 644-654.
[40] Moradi, A., & Izadpanah, M. (2022). Evaluation of the Behavior Factor of Vertically Irregular Moment Resisting Reinforced Concrete Frames Considering the Influence of Masonry Infill Walls. Amirkabir Journal of Civil Engineering, 54(5), 2005-2030

  • تاریخ دریافت 17 آبان 1404
  • تاریخ بازنگری 22 اردیبهشت 1405
  • تاریخ پذیرش 29 تیر 1405