ارزیابی آزمایشگاهی جزئیات جدید برای اتصال دال تخت پیش‌تنیده به ستون فولادی

رفیعی, سهند; حسینی, عبدالله; معرفت, محمدصادق

doi:10.22065/jsce.2020.234207.2162

ارزیابی آزمایشگاهی جزئیات جدید برای اتصال دال تخت پیش‌تنیده به ستون فولادی

نوع مقاله : علمی - پژوهشی

نویسندگان

¹ دانشجو دکتری، دانشکده مهندسی عمران، پردیس دانشکده‌های فنی، دانشگاه تهران، تهران، ایران

² دانشیار، دانشکده مهندسی عمران، پردیس دانشکده‌های فنی، دانشگاه تهران، تهران، ایران

³ استاد، دانشکده مهندسی عمران، پردیس دانشکده‌های فنی، دانشگاه تهران، تهران، ایران

10.22065/jsce.2020.234207.2162

چکیده

یکی از سیستم‌های سازه‌ای که در سال‌های اخیر در ساختمان‌ها مورد توجه روز‌‌افزون قرار گرفته است شامل دال تخت پیش‌تنیده و ستون فولادی می‌باشد. این سیستم از مزیت‌های اقتصادی و اجرایی قابل‌توجه برخوردار است ولی رفتار لرزه‌ای اتصال دال تخت به ستون، که اصولاً برای بار ثقلی طراحی می‌شود، با شک و تردید مواجه است. بدین لحاظ، این اتصالات بایستی از شکل‌پذیری کافی در برابر جابجایی‌های جانبی برخوردار باشند. گرچه در مراجع فنی، جزئیاتی برای اتصال دال تخت غیر‌‌پیش‌‌تنیده به ستون فولادی ارائه شده، که معمولاً شامل کلاهک برشی فولادی می‌باشد، ولی جزئیات خاصی برای دال تخت پیش‌تنیده، در ادبیات فنی ارائه ‌نشده است. در این مطالعه، جزئیات جدیدی برای اتصال دال تخت پیش‌تنیده به ستون فولادی ارائه شده است. این جزئیات شامل ورق‌های فولادی افقی، سخت‌کننده‌های فولادی قائم و پیچ‌های پر‌‌مقاومت برشی می‌باشد. به منظور ارزیابی جزئیات ارائه‌شده، نمونه آزمایشگاهی در مقیاس نیم ساخته ‌شده و تحت آزمایش رفت و برگشتی با دامنه افزایش‌یابنده قرار گرفته است. آزمایش نشان می‌دهد که اتصال ارائه‌شده می‌تواند جابجایی‌های‌ نسبتاً بزرگ جانبی تا حدود 6% دریفت را، بدون افت مقاومت و/یا از دست‌رفتن ظرفیت باربری ثقلی و/یا تخریب قابل‌توجه، تحمل نماید. طبق این مطالعه، جزئیات ارائه‌شده از شکل‌پذیری کافی در برابر بارگذاری جانبی و عملکرد لرزه‌ای مطلوب برخوردار است.

کلیدواژه‌ها

موضوعات

مهندسی سازه و زلزله

عنوان مقاله [English]

Experimental evaluation of new details for connections of post-tensioned flat slabs to steel columns

نویسندگان [English]

Sahand Rafiee ¹
Abdollah Hosseini ²
Mohammad Sadegh Marefat ³

¹ PhD candidate, School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran

² Associate Professor, School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran

³ Professor, School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran

چکیده [English]

One type of structural systems that has received growing attention in recent years, includes post-tensioned flat slabs and steel columns. This system has significant economic and professional advantages. But, seismic behavior of the connection between flat slab and steel column, which is principally designed for gravity loads, is in doubt. In this regard, these connections should have sufficient ductility under lateral deformations. Although details for the connections of nonprestressed slabs to steel columns are published in the technical references, which usually include steel shear heads, but specific details for post-tensioned slabs have rarely been published in the literature. In this study, new details have been proposed for the connections of post-tensioned flat slabs to steel columns. These details include horizontal steel plates, vertical steel stiffeners and high strength shear bolts. To evaluate the proposed details, a half scale test specimen was built and was subjected to lateral cyclic loading with increasing amplitude. The test shows that the proposed connection could withstand relatively large displacements up to a drift of 6%, without loss of strength and/or gravity bearing capacity and/or significant failure. According to this study, the proposed details have sufficient ductility under lateral loading and provide a favorable seismic performance.

کلیدواژه‌ها [English]

flat slab-steel column connection
post-tensioned flat slab
cyclic lateral loading
ductility
seismic details

مراجع

[1] Eder, M., Vollum, R., Elghazouli, A. (2012). Performance of ductile RC flat slab to steel column connections under cyclic loading, Engineering Structures, 36, 239-257.

[2] Bompa, D., Elghazouli, A. (2016). Structural performance of RC flat slabs connected to steel columns with shear heads, Engineering Structures, 117, 161-183.

[3] Yan, P., Wang, Y.C. (2016). Hybrid steel tubular column/flat slab construction-Development of a shear head system to improve punching shear resistance, Journal of Constructional Steel Research, 119, 154-168.

[4] Kim, J.-W., Lee, C.-H., Kang, T.H.-K. (2014). Shear head reinforcement for concrete slab to concrete-filled tube column connections, ACI Structural Journal, 111(3), 629-638.

[5] Lee, C.-H., Kang, T.H.-K., Kim, J.-W., Song, J.-K., Kim, S. (2019). Seismic performance of concrete-filled tube column-reinforced concrete slab connections with shear head keys, ACI Structural Journal, 116(2), 233-244.

[6] Lee, C.-H., Kim, J.-W., Song, J.-G. (2008). Punching shear strength and post-punching behavior of CFT column to RC flat plate connections, Journal of Constructional Steel Research, 64(4), 418-428.

[7] Su, Y., Tian, Y. Experimental study of RC slab-CFT column connections under seismic deformations, Challenges, Opportunities and Solutions in Structural Engineering and Construction, London, CRC Press, Taylor & Francis Group, pp. 337-342.

[8] Megally, S., Ghali, A., (2000). Seismic behavior of slab-column connections, Canadian Journal of Civil Engineering, 27(1), 84-100.

[9] Fernández Ruiz, M., Mirzaei, Y., Muttoni, A. (2013). Post-punching behavior of flat slabs, ACI Structural Journal, 110(5), 801-812.

[10] ACI Committee 318. (2019). Building code requirements for structural concrete and commentary (ACI 318-19), American Concrete Institute, Farmington Hills, Michigan.

[11] Kang, T.H., Wallace, J.W. (2006). Punching of reinforced and post-tensioned concrete slab-column connections, ACI Structural Journal, 103(4), 531-540.

[12] Megally, S., Ghali, A. (2000). Punching shear design of earthquake-resistant slab-column connections, ACI Structural Journal, 97(5), 720-730.

[13] Robertson, I.N., Durrani, A.J. (1993). Gravity load effect on seismic behavior of interior slab-column connections, ACI Structural Journal, 89(1), 37-45.

[14] Robertson, I.N., Durrani, A.J. (1991). Gravity load effect on seismic behavior of exterior slab-column connections, ACI Structural Journal, 88(3), 255-267.

[15] Anggadjaja, E., Teng, S. (2008). Edge-column slab connections under gravity and lateral loading, ACI Structural Journal 105(5), 541-555.

[16] Robertson, I.N., Kawai, T., Lee, J., Enomoto, B. (2002). Cyclic testing of slab-column connections with shear reinforcement, ACI Structural Journal, 99(5), 605-613.

[17] Kang, T.H., Wallace, J.W. (2005). Dynamic responses of flat plate systems with shear reinforcement, ACI Structural Journal, 102(5), 763-773.

[18] Han, S.W., Kee, S.-H., Park, Y.-M., Lee, L.-H., Kang, T.H.-K. (2006). Hysteretic behavior of exterior post-tensioned flat plate connections, Engineering Structures, 28(14), 1983-1996.

[19] Han, S.W., Kee, S.-H., Park, Y.-M., Ha, S.-S., Wallace, J.W. (2009). Effects of bottom reinforcement on hysteretic behavior of posttensioned flat plate connections, Journal of Structural Engineering, 135(9), 1019-1033.

[20] Gayed, R.B., Ghali, A. (2006). Seismic resistant joints of interior columns with prestressed slabs, ACI Structural journal, 103(5), 710-719.

[21] Ritchie, M., Ghali, A. (2005). Seismic resistant connections of edge columns with prestressed slabs, ACI Structural journal, 102(2), 314-323.

[22] Trongtham, N., Hawkins, N.M. (1980). Seismic resistance of unbonded post-tensioned flat plate construction, Proceedings of the World Conference on Earthquake Engineering, pp. 137-144.

[23] Dilger, W.H., Shatila, M. (1989). Shear strength of prestressed concrete edge slab–column connections with and without shear stud reinforcement, Canadian Journal of Civil Engineering, 16(6), 807-819.

[24] Foutch, D.A., GambleE, W.L., Sunidja, H. (1990). Tests of post-tensioned concrete slab-edge column connections, ACI Structural Journal, 87(2), 167-179.

[25] Martinez-Cruzado, J.A. (1993). Experimental study of post-tensioned flat plate exterior slab-column connections subjected to gravity and biaxial loading, PhD, Department of Civil Engineering, University of California at Berkeley, CA.

[26] Qaisrani, A. (1995). Interior post-tensioned flat plate connections subjected to vertical and biaxial lateral loading, PhD, Department of Civil Engineering, University of California at Berkeley, CA.

[27] Han, S.W., Kee, S.-H., Kang, T.-K., Ha, S.-S., Wallace, J.W., Lee, L. (2006). Cyclic behaviour of interior post-tensioned flat plate connections, Magazine of Concrete Research, 58(10), 699-711.

[28] Himawan, A., Teng, S. (2014). Cyclic behavior of post-tensioned slab-rectangular column connections, ACI Structural Journal, 111(1), 177-187.

[29] Kang, T. H.-K., Robertson I. N., Hawkins N. M., and Lafave J. M. (2008). Recommendations for Design of Post-Tensioned Slab-Column Connections Subjected to Lateral Loading, PTI Journal, 6(1), 45-59.

[30] ASCE/SEI 7. (2016). Minimum design loads and associated criteria for buildings and other structures (ASCE 7-16), American Society of Civil Engineers, Reston, Virginia.

[31] ACI Committee 374. (2005, Reapproved 2014). Acceptance criteria for moment frames based on structural testing and commentary (ACI 374.1-05), American Concrete Institute, Farmington Hills, Michigan.