بهبود عملکرد میانقاب‌های بنایی تقویت شده با وال-پست فولادی تحت اثر فواصل و جرم‌های مختلف بارگذاری انفجار

نوع مقاله : علمی - پژوهشی

نویسندگان

1 گروه آموزشی سازه، دانشکده عمران، دانشگاه صنعتی جندی شاپور، دزفول

2 گروه آموزشی سازه، دانشکده عمران، دانشگاه صنعتی جندی شاپور،دزفول

چکیده

با افزایش حملات انفجاری و ضرورت آمادگی دفاعی ، می‌توان راهکارهایی برای ارتقای ایمنی و مقاوم‌سازی اعضای غیرسازه‌ای پیش بینی و کارایی آن ها را نیز بررسی کرد. در این مقاله عملکرد غیرخطی یک قاب بتن مسلح با میانقاب غیرسازه‌ای تقویت شده با وال-پست فولادی تحت اثر بار انفجار بررسی شده است. برای این کار یک در گام اول قاب بتنی با میانقاب‌های بنایی تقویت شده با وال-پست فولادی بر اساس آخرین توصیه‌ی نسخه‌ی آیین‌نامه‌های طراحی لرزه‌ای ایران ، در نرم‌افزار المان محدودی ABAQUS تحت بارگذاری دو خرج انفجاری kg300 و kg1000 به روش فشار معادل انفجار در سطح زمین در فواصل 5، 10 و 15متر از پای سازه قرار گرفته و پاسخ جابه‌جایی نسبی میانقاب‌ها و انرژی مستهلک‌شده در کل مدل مورد مطالعه قرار گرفته است. در گام دوم به ضرورت تقویت این سیستم با اتخاذ دو راهبرد افزایش شماره مقطع وال-پست و کاهش فواصل وال-پست‌ها پرداخته شده است. نتایج نشان داده است که جابه‌جایی نسبی میانقاب نظیر در مدل با راهبرد افزایش شماره‌ی مقطع وال-پست‌‌ها، تحت خرج kg1000و kg300 در فاصله‌ی 5متر با افزایش مقطع نبشی از L60x60x6 mm به L80x80x8 mm به ترتیب %34.20 و %48.25 کاهش یافته است. این کاهش در مدل با راهبرد کاهش فواصل وال-پست‌‌ها، تحت خرج kg1000 و kg300 در فاصله‌ی 5متر به ترتیب %5.51 و %3.53 بدست آمد که نسبت به مقدار کاهش راهبرد اول بیش از 2برابر بود. .همچنین انرژی مستهلک شده در مدل با راهبرد کاهش فواصل نسبت به مدل با مقطع L80x80x8 mm تحت انفجار kg1000، بیش از 2.4 بدست آمده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Performance Improvement of Masonry Infill Walls Strengthened With Steel Wall-Post Under Different Charges & Different Distances of Explosion Loading

نویسندگان [English]

  • SeyedVahid RazaviTosee 1
  • Armin Barzin 2
1 Civil Eng. Department, Jundi-shapur University of Technology, Dezful, Iran
2 Civil Eng Department, Jundi-shapur University of Technology, Dezful, Iran
چکیده [English]

With the increase in explosive attacks and the need for defensive preparedness, it is possible to consider strategies to improve the safety and resilience of non-structural members and their efficiency. In this paper, the nonlinear performance of a reinforced concrete frame with non-structural steel wall-reinforced interlayer under blast load is investigated. For this, in the first step, a concrete frame with steel wall-reinforced masonry frames, according to the latest recommendation of the Iranian seismic design code, in ABAQUS finite element software under the load of two explosive charges of 300 and 1000 kg by equivalent pressure method. The blast was located at distances of 5, 10, and 15 meters from the base of the structure, and the relative displacement response between the interfaces and the dissipated energy in the whole model were studied. In the second step, the necessity of strengthening this system has been discussed by adopting two strategies: increasing the cross-sectional number of wall-posts and reducing the distances of wall-posts. The results show that the relative displacement of peer-to-peer in the model with the strategy of increasing the cross-sectional number of wall-posts, at the expense of 1000 kg and 300 kg at a distance of 5 m by increasing the angle cross-section from L60x60x6 mm to L80x80x8 mm by 34.20%, respectively. And decreased by 48.25%. This reduction was achieved in the model with the strategy of reducing the distances of the wall posts at the expense of 1000 and 300 kg at a distance of 5 meters, respectively 5.51% and 3.53%, which was more than 2 times the amount of reduction of the first strategy. Also, the depleted energy in the model with the strategy of reducing distances compared to the model with a cross-section of L80x80x8 mm under 1000 kg explosion, more than 2.4 has been obtained.

کلیدواژه‌ها [English]

  • strengthening
  • Masonry infilled-wall
  • Seismic Design
  • Explosive Charge
  • Explosive Loading
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