اثر خاک بر پاسخ لرزه ای سازه های بتنی با مهاربند ضربدری فلزی

نوع مقاله : علمی - پژوهشی

نویسندگان

1 کارشناس ارشد مهندسی عمران، گروه مهندسی عمران، واحد بوشهر، دانشگاه آزاد اسلامی، بوشهر، ایران

2 استادیار، گروه مهندسی عمران، واحد بوشهر، دانشگاه آزاد اسلامی، بوشهر، ایران

چکیده

در سال‌های اخیر، استفاده از سیستم مهاربند فولادی در سازه‌های بتن مسلح گسترش یافته است. سیستم مهاربندی می‌تواند به ‌طور مؤثر جهت بهسازی سازه‌های بتنی موجود نیز استفاده شود. لحاظ نمودن اندرکنش خاک - سازه در آنالیز سازه نسبت به حالتی که خاک زیر سازه صلب در نظر گرفته شود موجب تغییر در رفتار سازه هنگام تحریک لرزه‌ای می‌شود. مطالعه حاضر حاصل نگرش واقع‌بینانه به مسأله اثرات خاک بررفتار لرزه‌ای سازه‌های بتنی با مهاربند فولادی می‌باشد. در این تحقیق با در نظر گرفتن سازه بتنی 6 طبقه، بهسازی شده با مهاربند ضربدری بر روی سه نوع خاک C، D وE مطابق آیین‌نامه ASCE7-16 ، تحت رکوردهای زلزله مناسب به بررسی اثر اندرکنش خاک - سازه پرداخته شده است. در مدل‌سازی، برای سازه رفتار غیرخطی و برای خاک رفتار خطی و غیرخطی فرض شده و تحلیل دینامیکی غیرخطی اندرکنش خاک - سازه با استفاده از روش مستقیم و مدلسازی هندسی دوبعدی در نرم افزار اپنسیس انجام شده و پاسخ سازه با در نظر گرفتن دو حالت پایه صلب و پایه انعطاف پذیر مقایسه گردیده است. نتایج نشان می‌دهد درنظر گرفتن اندرکنش خاک و سازه در مدل‌های بهسازی شده به وسیله مهاربند فولادی بسته به نوع خاک باعث افزایش زمان تناوب در برخی موارد تا حدود 72 % و کاهش برش پایه تا حدود 49% نسبت به حالت بستر صلب در سازه می‌گردد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of soil on the seismic response of concrete structures with steel X-bracing

نویسندگان [English]

  • Sara Alizadeh 1
  • Hadi Dashti 2
1 M.Sc. of Civil Engineering, Department of Civil Engineering, Bushehr branch, Islamic Azad University, Bushehr, Iran
2 Assistant Professor, Department of Civil Engineering, Bushehr branch, Islamic Azad University, Bushehr, Iran
چکیده [English]

In recent years, the use of steel bracing system in reinforced concrete structures has expanded. The bracing system can also be used effectively to improve existing concrete structures. Considering the soil -structure interaction in the analysis of the structure compared to the case where the soil of the substructure is considered rigid causes a change in the behavior of the structure during seismic excitation. The present study is the result of a realistic approach to the problem of soil effects on the seismic behavior of concrete structures with steel bracing. In this research, considering the 6-story concrete structure, improved with X-bracing on three types of soil C, D and E according to ASCE7-16 standard, under appropriate earthquake records, the effect of soil-structure interaction has been investigated. In modeling, nonlinear behavior is assumed for structure and linear and nonlinear behavior is assumed for soil and nonlinear dynamic analysis of soil -structure interaction is performed using direct method and two-dimensional geometric modeling in Opensees software and the response of structure by considering two The rigid base and the flexible base are compared. The results show that considering the soil -structure interaction in models improved by steel bracing according to the type of soil, increases the period in some cases up to about 72% and reduces the base shear to about 49% compared to the rigid bed in the structure.

کلیدواژه‌ها [English]

  • Concrete structure
  • Steel bracing
  • Soil-structure interaction
  • Seismic
  • Opensees
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