اثر بازشو و فواصل برش‌گیرها در رفتار دیوار برشی مرکب

نویسندگان
1 دانشجوی دکتری دانشگاه تربیت مدرس
2 مدرس
چکیده
ددیوارهای برشی سیستمی مقاوم در برابر نیروهای جانبی همچون باد و زلزله می‌باشند. با توجه به شکل‌پذیری و مقاومت جانبی مناسبی که دیوارهای برشی فولادی دارند، این نوع دیوارها در دهه‌های اخیر مورد توجه مهندسین و محققین قرار گرفته‌اند. در صورتیکه تسلیم برشی قبل از کمانش ورق جان دیوار رخ دهد، قابلیت جذب انرژی دیوار بیشتر خواهد شد. تقویت ورق جان دیوار برشی فولادی موجب تسلیم برشی قبل از کمانش ورق می‌گردد. بمنظور تقویت ورق دیوار می‌توان از سخت‌کننده‌های فولادی و یا لایه‌ای از بتن استفاده کرد. دیوار برشی فولادی که از یک یا دو لایه بتنی جهت افزایش مقاومت خارج از صفحه آن استفاده شود، را دیوار برشی مرکب می‌گویند. با توجه به مطالعات اندکی که در زمینه این نوع دیوارها انجام گرفته است، در این مطالعه به بررسی اثر بازشو و فواصل برش‌گیرها در رفتار دیوار برشی مرکب پرداخته خواهد شد. ابتدا یک دیوار برشی مرکب برای ساختمان 10 طبقه طراحی شده و پس از انتخاب طبقه فوقانی آن و ساخت چندین مدل اجزای محدود در نرم‌افزار Abaqus، به بررسی آنها پرداخته شده است. نتایج نشان می‌دهد که برخلاف دیوار برشی فولادی که بازشو در مرکز نسبت به کناره دیوار بیشتر مقاومت را کاهش می‌دهد، بازشو در گوشه‌های دیوار برشی مرکب نسبت به میانه آن باعث کاهش مقاومت می‌شود. همچنین با کاهش فاصله بین برش‌گیرها ظرفیت دیوار برشی مرکب افزایش می‌یابد.

کلیدواژه‌ها


عنوان مقاله English

The Effect of Opening and Stud Spacing on Composite Shear Wall Behavior

نویسندگان English

Hamid Reza Kazemi Nia Korrani 1
1 1 2
2 1
چکیده English

Shear walls are resistant to lateral forces such as wind and earthquake. In recent decades, because of proper ductility and high strength of steel shear walls, engineers and researchers are interested to these walls. If the shear yielding occurs before buckling of web plate of wall, the wall will absorb more energy. Reinforcing steel plate shear wall would cause shear yielding occurs before buckling. In order to strengthen of wall can be used steel stiffeners or one layer of concrete. Steel shear walls with a layer of concrete to increase the strength out of plane called composite shear wall. Composite shear walls consist of a thin steel plate, two columns and two horizontal floor beams with one or two concrete layers. Considering the few studies that have been done on this type of walls, in this study, the effect of opening and stud spacing will be discussed in the behavior of the composite shear wall. Firstly, the 10-storey building with composite shear walls designed. Then upper floor selected and finite element models of this floor modeled with Abaqus. The models are one span and one story that length of span (inside into columns) and a height of story (the inside of the beams) is 3 m. Beams and columns are IPB280 and thickness of web plate and concrete layer are 2 and 100 mm respectively. It should be mentioned, to prevent local buckling column flange at the beam-column connection, in line of beam flange, continuity plate is considered. In this study to ensure the accuracy of the finite element model and ability of Abaqus to accurately estimate the actual behavior of shear walls, several shear walls model and analyze, then their results were compared with the results of the tests in the previous studies (Lubell’s test and Valizadeh’s experimental model). The results show that there is little difference between the experimental results and finite element results. So by taking a little difference can be concluded that the finite element results are acceptable.
In order to compare the results of finite element models of composite and steel shear wall and steel moment frame, boundary elements and also load all three models are considered equal. Compare the results show that, on a constant displacement, the base shear in the steel shear wall is about 120% more than moment frame. Also, the base shear in the composite shear wall is 23% more than steel shear wall.
Considering the results, it is evident that by reducing the distance between the studs, wall strength increases. Also, increasing web plate thickness cause to increases the capacity of the composite shear walls. Opening has always been the creation of composite shear wall resistance decreases. Opening at the sides and corners further reduces the resistance. This is unlike steel shear walls. At the end of this paper was to effect of the stud positions on the composite shear wall behavior. The results indicated that the studs closer to the external environment, resistance of composite shear wall increases.

In order to compare the results of finite element models of composite and steel shear wall and steel moment frame, boundary elements and also load all three models are considered equal. Compare the results show that, on a constant displacement, the base shear in the steel shear wall is about 120% more than moment frame. Also, the base shear in the composite shear wall is 23% more than steel shear wall.
Considering the results, it is evident that by reducing the distance between the studs, wall strength increases. Also, increasing web plate thickness cause to increases the capacity of the composite shear walls. Opening has always been the creation of composite shear wall resistance decreases. Opening at the sides and corners further reduces the resistance. This is unlike steel shear walls. At the end of this paper was to effect of the stud positions on the composite shear wall behavior. The results indicated that the studs closer to the external environment, composite shear wall resistance increases.

کلیدواژه‌ها English

Composite shear wall
opening
Stud
ductility
finite element method
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