ارزیابی عملکرد سازه فولادی ده طبقه دارای جداساز لرزه‌ای تحت بارهای انفجار

نوع مقاله : علمی - پژوهشی

نویسندگان

1 دانشیار، دانشگاه صنعتی نوشیروانی بابل

2 دانشگاه نوشیروانی

3 دانشگاه قم

چکیده

وقوع حملات تروریستی و بمب‌گذاری در سال‌های اخیر، اهمیت ایمنی سازه در برابر بار انفجار را بیشتر از گذشته نشان می‌دهد. انفجار از جمله حوادث نادری است که می‌تواند خسارات زیادی را در طول عمر مفید ساختمان‌ها در پی داشته باشد. بررسی رفتار سازه‌ها تحت بار انفجار می‌تواند به تصمیمات مدیریتی در جهت امنیت سازه‌ها کمک شایانی نماید. در این تحقیق رفتار سازه‌های فولادی با جداسازی لرزه‌ای از نوع LRB در سناریوهای مختلف انفجار با استفاده از مفهوم بالانس انرژی بررسی‌شده است. دو تیپ سازه‌ی فولادی 10 طبقه‌ی جداسازی شده و سازه با پای ثابت پس از طراحی در معرض 12 نوع بارگذاری انفجار قرار گرفته است. در ابتدا عملکرد سازه‌ها تحت این بارگذاری‌ها بررسی و دوران مفاصل پلاستیک و دریفت سازه‌ها ارزیابی شده و در ادامه با استفاده از منحنی‌های تاریخچه زمانی انرژی‌های تلف شده و جذب‌شده‌ی موجود در سازه، بالانس انرژی در هریک از سناریوها بررسی و نقش جداسازها در ایجاد بالانس انرژی بررسی‌شده است. نتایج نشان داده است انرژی کرنشی پلاستیک تلف شده در جداسازهای لرزه‌ای باعث شده است انرژی تلف شده توسط سایر اعضا کاهش یابد و میزان خسارت در آن‌ها نیز کم شود. همچنین درصد انرژی های داخلی در اتلاف انرژی ناشی از اعمال بار انفجار نیز مورد ارزیابی قرار گرفته است. در سازه های دارای جداساز لرزه ای سهم اتلاف انرژی المان های تیر و ستون کمتر از سازه با پای ثابت است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Evaluation of the performance of a 10 story steel structure with Base Isolation under blast loads

نویسندگان [English]

  • Hamidreza Tavakoli 1
  • majid moradi 2
  • miad kiandoust 3
1 Associate Professor, Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol, Iran
2 noshivani
3 university of ghom
چکیده [English]

The occurrence of terrorist attacks and bombings in recent years has shown the importance of constructive safety against blast loading more than ever before. Blast is one of the rare events that can cause many damages to the buildings during their lifespan. Investigating the behavior of structures under blast load can help to make managerial decisions for the safety of structures. In this research, the behavior of steel structures with seismic isolation of LRB type in different explosion scenarios was investigated using the concept of energy balance. Two types of 10-story steel structures with isolated and fixed-bases have been subjected to 12 types of blast loadings after designing. Initially, the performance of the structures under these loadings and the rotation of the plastic joints and drift of structures were evaluated and then, using the time history curves the depreciated and absorbed energies of the structure, balance of energy in each scenario are studied and the role of isolators in the creation of energy balance is investigated. The results show that the existence of depreciated plastic strain energy in seismic isolators reduce depreciated energy in other members and the amount of their damage will be decreased. Also, the percentage of internal energy in the energy loss caused by the explosive charge has also been evaluated.
In structures with a seismic separation, the energy loss ratio of the elements of the beam and column is less than that of the fixed foot structure.

کلیدواژه‌ها [English]

  • Base isolation
  • Blast loading
  • Energy balance
  • steel structure
  • Structural performance
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