بررسی نحوه آرایش جداگرهای لرزه ای در ساختمان های کوتاه مرتبه

نویسندگان

1 دانشگاه قم

2 دانشگاه سمنان

چکیده

جداسازی لرزه ای یک روش طراحی مقاوم لرزه ای است که براساس کاهش تقاضای لرزه ای به جای افزایش ظرفیت لرزه ای می باشد. در این مقاله، پاسخ لرزه ای سازه جداسازی شده مورد بررسی قرار گرفته است. تاثیر سیستم جداساز بستگی به خصوصیات دینامیکی حرکات زمین و ساختمان روسازه دارد. به منظور ارزیابی پاسخ غیرخطی سازه های جداسازی شده، مدل های سه بعدی تحلیلی غیرخطی با خصوصیات متفاوت انتخاب و تحت زلزله های مطرح مورد تحلیل قرار گرفتند. همچنین به منظور بررسی رفتار بهینه سیستم، انواع مختلف جداساز شامل سیستم لاستیکی با هسته سربی و سیستم آونگ اصطکاکی بین روسازه و فونداسیون مدل‌سازی شد. مطالعه پارامتریک بر روی برش پایه، شتاب و تغییرمکان مدل های جداسازی شده متمرکز شده است. مقایسه ای بین پاسخ هیسترزیس مدل ها به عنوان معیار اصلی اتلاف انرژی سیستم انجام شده است. نتایج نشان می دهد که مدل استفاده شده با 25 درصد از جداگر آونگ اصطکاکی بهترین پاسخ سازه‌ای را در برابر نیروهای لرزه ای می دهد.

کلیدواژه‌ها


عنوان مقاله [English]

EVALUATION OF BASE-ISOLATOR TYPE DISTRIBUTION IN LOW-RISE BUILDINGS

نویسندگان [English]

  • S.R. Hoseini Vaez 1
  • H. Naderpour 2
چکیده [English]

Seismic base isolation is an earthquake resistant design method that is based on decreasing the seismic demand instead of increasing the seismic capacity. In this paper, the seismic response of base-isolated structures is numerically investigated. The effectiveness of an isolation system depends upon the dynamic characteristics of earthquake ground motion and the building superstructure. In order to evaluate the dynamic response of nonlinear base-isolated structures, different detailed 3D nonlinear analytical models with different characteristics are developed and analyzed under significant and strong motion earthquakes. Also in order to have the optimized behavior of system, different types of isolators including Lead-Rubber Bearing (LRB) and Friction-Pendulum (FPS) isolators were simulated between the superstructure and the foundation so as to provide lateral flexibility and energy dissipation capacity. Providing an optimized arrangement of different types of isolators in the structure is important since it affects the structural responses to earthquakes. The parametric study is concentrated on base shear, accelerations and displacements of isolated models. Also the comparison between hysteretic responses of models as a main criterion for energy dissipation of system has been investigated and evaluated. Results show that the model with FPS ratio of 25% has the best structural response against seismic loads.

کلیدواژه‌ها [English]

  • Base-isolator
  • Lead-rubber Bearing
  • Friction-pendulum
  • Low-rise building
 

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