بررسی تاثیر پارامترهای مختلف مدل‌سازی بر رفتار قاب‌های خمشی فولادی ویژه

نوع مقاله : مقاله پژوهشی

نویسندگان

1 فارغ التحصیل کارشناسی ارشد مهندسی عمران - سازه، دانشکده‌ی فنی و مهندسی، دانشگاه محقق اردبیلی، اردبیل، ایران،

2 گروه عمران دانشکده فنی و مهندسی دانشگاه محقق اردبیلی اردبیل ایران

چکیده

در این مقاله، تأثیر پارامترهای مختلف در جزئیات مدل‌سازی از قبیل اتصالات تیر – ستون، نوع خاک و فونداسیون بر پاسخ لرزه‌ای قابهای خمشی فولادی مورد بررسی قرار گرفته است. بدین منظور، ساختمان پنج طبقه با سیستم قاب خمشی فولادی ویژه واقع بر دو نوع خاک متفاوت II و IV در نظر گرفته شده است. دو نوع فونداسیون سطحی، نواری و منفرد، برای این ساختمان با ضریب اطمینان سه در ظرفیت باربری طراحی گردیده است. برای مدل‌سازی اتصالات تیر – ستون، اتصالات گیردار از پیش تأیید شده ی پیچی به کمک ورق‌های روسری و زیرسری بکار رفته است. مدل‌سازی اجزا محدود حالت‌های مفروض توسط نرم افزار OpenSees صورت گرفته و از تحلیل‌های دینامیکی غیرخطی توسط هفت شتاب نگاشت زلزله جهت بدست آوردن پاسخ‌ها استفاده شده است. در مدل‌هایی که اثر اندرکنش خاک – فونداسیون - سازه برای آن ها لحاظ گردیده است، رفتار غیرخطی خاک به صورت فنرهای غیرخطی وینکلر مدل‌سازی شده است. نتایج حاصله حاکی از آن است که با لحاظ اثر اتصالات و خاک در مدل های واقع بر خاک نوع IV ،حداکثر تغییرمکان نسبی نسبت به مدل‌های بدون لحاظ آن‌ها افزایش و حداکثر برش پایه کاهش می‌یابد و در مدل‌های واقع بر خاک نوع II ،حداکثر مقدار این پارامترها کاهش می یابد. همچنین تأثیر تغییر نوع فونداسیون در مدل‌های واقع بر خاک نوع IV بیشتر از مدل‌های واقع بر خاک نوع II است. بنابراین لحاظ اتصالات تیر – ستون، نوع فونداسیون و اندرکنش خاک – فونداسیون – سازه در مدل‌سازی تأثیر بسزایی بر پاسخ های غیرخطی قاب‌های خمشی فولادی دارد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

An investigating into the effect of various modeling parameters on the behavior of special steel moment frames

نویسندگان [English]

  • Maryam Zare Aghblagh 1
  • Hamed Rahman Shokrgozar 2
1 M.Sc. of Structural Engineering, Faculty of Engineering, Iran, University of Mohaghegh Ardabili
2 civil engineering, engineering and technology department of mohaghegh ardabili university, Ardabil, iran
چکیده [English]

In this paper, the effect of various modeling parameters such as beam-column connections, soil and shallow foundation types are studied to assess the seismic response of steel moment frames. For this purpose, five-story special steel moment frames with two different soil types (II and IV) were considered. The footing and strip shallow foundations were designed for these buildings, with a safety factor of three. Prequalified bolted flange plate connections were used in these buildings. The finite element models were developed using OpenSees software considering soil – foundation – structure interaction. The seismic performance of SMFs was evaluated using nonlinear time history analyses, through seven far–fault ground motions. Nonlinear behavior of soil was modeled by nonlinear Winkler springs. The numerical results showed that in the models that considered beam-column connections, SFSI and soil type IV, the maximum inter-story drift was more, compared to models without connections and with fixed based conditions. The maximum base-shear force of structures in the mentioned models was reduced. In models, that structures rested on soil type II, maximum values of these two parameters were diminished. The effect of foundation type in models resting on the soil type IV was more than models with soil type II. Generally, connections, foundation type and soil-foundation-structure interactions have a great influence on the nonlinear responses of steel moment frames.

کلیدواژه‌ها [English]

  • Special steel moment frame
  • Soil – foundation – structure interaction
  • fixed connections
  • soil and foundation type
  • time history dynamic analysis
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