ارزیابی تاثیر رفتار لرزه‌ای اتصالات مفصلی و گیردار در سازه‌های بتن مسلح براساس تغییر درصد آرماتور طولی در مقطع تیر

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه عمران سازه ، دانشکده فنی و مهندسی، دانشگاه آزاد واحد تبریز

2 دانش آموخته کارشناسی ارشد عمران، سازه، واحد قشم، دانشگاه آزاد اسلامی، قشم، ایران

چکیده

اتصالات تیر - ستون در قابهای بتن مسلح از جمله عناصر کلیدی در تعیین رفتار سازه در مقابل انواع بارها می­باشد. نقش این اتصالات در مقابل بارهای جانبی بخصوص رخدادهای قوی لرزه­ای بسیار مهم بوده و رفتار سازه­های بتن مسلح در زلزله های گذشته نشان می­دهد که اتصالات تاثیر قابل توجهی در میزان و شدت خرابی­های حاصله داشته­اند. از سوی دیگر تجارب بدست آمده در زلزله­های گذشته منجر به در نظر گرفتن تمهیدات جدید طراحی اتصال در آیین نامه­های فعلی شده است. علی رغم اهمیت اتصالات مفصلی و همچنین استفاده فراوان از آنها در سازه­های فولادی، به علت عدم وجود جزئیات مطمئن کاربرد آنها در سازه­های بتنی بسیار اندک است. در این مقاله رفتار اتصالات در قاب­های بتنی ساختمانی در دو حالت گیردار و مفصلی و برای درصدهای مختلف تسلیح مقطع تیر در محیط نرم افزار ABAQUS  مدلسازی شده و مورد مقایسه قرار گرفته است. نتایج این تحقیق نشان دهنده آن است که با افزایش درصد آرماتورهای طولی در مقطع تیر در حالت استفاده از اتصالات گیردار منجر به افزیش شکل پذیری اتصال گردیده است. با این حال با افزایش درصد آرماتور و ثابت ماندن ابعاد هندسی تیر در نهایت شکل پذیری به تدریج دچار کاهش شده است.همچنین با افزایش درصد آرماتور در مقطع تیر در حالت استفاده از اتصالات مفصلی منجر به افزیش ظرفیت نهایی اتصال به صورت پیوسته ولی بسیار تدریجی می‌گردد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of the Comparative Effect of Seismic Behavior of Hinge and Fixed Connections on RC Structures Based on the Change in Reinforcement Ratio

نویسندگان [English]

  • yousef zandi 1
  • Ruhedin Gasemi Sardareh 2
1 Assistant Professor, Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
2 MSc in Civil Engineering,Structural Engineering from Geshm Branch, Islamic Azad University, Geshm, Iran.
چکیده [English]

 
Beam-Column joints in reinforced concrete frames are one of the key elements in determining the structural behavior of a variety of loads. The role of these joints against lateral loads, especially strong seismic events, is very important and the behavior of reinforced concrete structures in past earthquakes indicates that Connections have had a significant impact on the extent and severity of the failures. On the other hand, the experience gained in past earthquakes has led to the consideration of new interconnection design schemes in the current regulations. Despite the importance of joint joints and their extensive use in steel structures, due to the lack of precise details on their use in concrete structures, they are very small. In this paper, the behavior of joints on concrete frames in two types of absorption and bonding and for various reinforced sections of reinforced beams is modeled and compared in ABAQUS software environment. The results of this study indicate that increasing the percentage of the armature at the cross section in the case of the use of clamping joints has led to an increase in connective ductility. However, by increasing the reinforcement of the reinforcement and maintaining the geometric dimensions of the beam, the ultimate degree of ductility is gradually reduced. Also, with the increase in the diameter of the reinforcement in the beam during the use of joint joints, it increases the final capacity of the connection continuously but very gradually it turns out.
 

کلیدواژه‌ها [English]

  • : joint joints
  • bonding connection
  • seismic behavior of joints
  • armed cross section percentage of reinforced beam
 
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