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Register a new userComparison Between Filled and Hollow X-Shape Plates in Dampers ADAS (Damping Ratio & Ductility Ratio & Energy Dissipation Ratio)
مقارنة بين الصفائح المصمتة و المفرغة - بشكل حرف X- المستخدمة في المخمّدات المعدنية ADAS من حيث (نسبة التخامد & نسبة المطاوعة & نسبة تبديد الطاقة)
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Tishreen University ورقة بحثية
Publication date
2015
fields
Structural Engineering
and research's language is
العربية
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Shamra Editor
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تُقدم هذه المقالة دراسة عددية و تحليلية لمجموعة من الصفائح بشكل حرف X بهدف اختيار الصفيحة الأفضل للعمل كمخمّد معدني من النمط ADAS و الذي يهدف بدوره لامتصاص و تخميد الطاقة الزلزالية في الجمل الإطارية للمنشآت. ُتمتص و تُخمد الطاقة من خلال دخول الصفيحة دفعة واحدة في مرحلة اللدونة تحت تأثير تشوهات قص دورية لامرنة, على اعتبار أن الصفيحة مثبتة بوثاقة تامة من الطرفين. يتم إثبات فعالية الصفائح المدروسة من خلال بناء خمسة نماذج حاسوبية ضمن بيئة برنامج ABAQUS و مقارنة النتائج مع نتائج التحليل للانهيار اللدن. حيث أظهر التحليل اللاخطي أن جميع الصفائح تتمتع بسلوك هيستيري مستقر و تقوم بامتصاص الطاقة بدرجة ممتازة، و ذلك عند تعرضها لانتقالات دورية قسرية. و الجدير بالذكر أيضا أن الأبعاد الهندسية الخارجية للصفائح و خصائص الفولاذ المستخدم هي حصيلة أبحاث عالمية محكمة، في حين تهتم هذه المقالة بدراسة آثر وجود فتحات صغيرة - دائرية و طولية - في هذه الصفائح لرفع جدوى التخميد بأعلى درجة ممكنة.
This article summarizes a numerical and mathematical comparison between filled and hollow X-shape plates to develop a new steel energy dissipative damper for structures protection of earthquakes. The plate is a weld from two ends. Energy is dissipated through flexural yielding when the plate is subjected to inelastic cyclic deformation. The performance of the plate was verified by five models by software ABAQUS and plastic mechanism analysis. Results showed that the plate exhibited stable hysteresis and dissipate energy with excellent values. It is Important to say all dimensions of plates and quality of steel are verified by international articles. This article's interest lies in studying the effect of openings on plate's dissipation energy.
References used
BERGMAN, D.M.; GOEL S.C. Evaluation of cyclic testing of steel plate devices for added damping and stiffness. Report no. UMCE87-10, Ann Arbor (MI, U.S.A), 1987
BOARDMAN, P.R.; WOOD B.J.; CARR A.J. A cross braced structure with energy dissipaters. Bulletin of the New Zealand National Society for Earthquake Engineering, Vol.16, N.2, 1982
CLARK, P.W; AIKEN, I.D.; TAJIRIAN F.; KASAI, K. Design procedures for buildings incorporating hysteretic damping devices, 1999
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Si:N ratios from spring to summer of 2010 and 2011. For this purpose, natural
Phytoplankton was cultured in mesocosmic experiments at two stations in the north
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affected the species composition of the diatoms themselves, where the species
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under different Si:N ratios.
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