اثر تقویت دیوار برشی بتنی با کمک مهاربند کمانش‌ناپذیر تحت نگاشت حوزه دور و نزدیک

نوع مقاله : مقاله کامل پژوهشی

نویسنده

گروه مهندسی عمران، واحد مهدیشهر، دانشگاه آزاد اسلامی

چکیده

زلزله‌های نزدیک گسل پالس‌دار در مقایسه با زلزله‌های دور از گسل، پتانسل بیشتری برای ایجاد خرابی در سازه‌ها را دارند. در این مقاله، اثر زلزله‌های دور از گسل و نزدیک گسل بر پاسخ سازه‌های با دیوار برشی بتن مسلح تقویت شده با مهاربند‌های کمانش­ناپذیر در ساختمان‌های با ارتفاع متوسط و بلند با لحاظ نمودن ویژگی‌های هرکدام از این المان‌ها مورد مطالعه قرار می‌گیرد. این سیستم سازه­ای یک سیستم ترکیبی به شمار می‌رود. در این پژوهش، سازه‌های مدل‌های مورد نظر، با به کارگیری روش تحلیل دینامیکی طیفی در سطح زلزله طرح و آیین­نامه‌های معتبر طراحی شدند. در ادامه، مدل غیر خطی سازه‌ها تهیه شدند. در مدل­سازی دیوار از المان‌های فایبری با قابلیت توسعه پلاستیسیته استفاده شد. تحلیل تاریخچه زمانی غیر خطی تحت اثر رکورد‌های دور و نزدیک گسل در سطح حداکثر زلزله محتمل انجام شد و پاسخ سازه‌ها بررسی و قیاس شد. نتایج نشان داد در تراز پایه، مقدار برش سهم دیوار در حوزه نزدیک و حوزه دور به ترتیب بیش از سه برابر و دو برابر مقدار برش سهم مهاربند‌ها است. مقادیر نسبت کرنش مهاربند به کرنش تسلیم مهاربند تحت زلزله نزدیک گسل به طور متوسط حدود 22 است که این نسبت برای حوزه دور به طور متوسط حدود 12 است.

کلیدواژه‌ها


عنوان مقاله [English]

Effect of Near and Far Fault Earthquake on the Shear Wall and Buckling Restrained Braces

نویسنده [English]

  • Hamid Beiraghi
Department of Civil Engineering, Mahdishahr Branch, Islamic Azad University
چکیده [English]

Near fault earthquakes compared to far-fault earthquakes have greater potential to create damage in structure. In this paper, the effect of far fault and near fault events on structural response of reinforced concrete shear wall with buckling restrained brace frame in tall and mid-rise buildings is studied. In the modeling, the specification of the reinforced shear wall and the buckling restrained braces is used. This kind of structural system is essentially a combined system. In this study, the structural system of the considered buildings is designed by using the valid codes and using response spectrum analysis method. Then, the nonlinear model is prepared. In the numerical model of the walls, the fiber type elements is used. The nonlinear time history analysis is implemented subjected to the far fault and near fault earthquakes. Finally, the responses of the structures are analyzed and compared. The results showed that, in the level of the base, the amount of shear demand of the wall share in the near field and far field is more than three times and twice the amount of shear demand share of braces. On average, the values of the strain demand ratio to the yielding strain in the core of the braces under the near field earthquakes was about 22, which is approximately 12 for the far field earthquakes.

کلیدواژه‌ها [English]

  • Near and far fault earthquake
  • reinforced concrete wall
  • buckling restrained braces
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