تحلیل پارامتریک خیز تیرهای بتن مسلح تحت بار انفجار

نوع مقاله : عمران - سازه

نویسندگان

1 استادیاردانشگاه صنعتی مالک اشتر، تهران ، ایران

2 کارشناسی ارشد دانشگاه صنعتی مالک‌اشتر، تهران، ایران

چکیده

جهت رفع طولانی‌شدن فرایند تحلیل و طراحی سازه‌­های بتنی در برابر بار انفجار و ارائه یک روش سهل­‌الوصول و مستقیم برای محاسبه پاسخ تیرهای بتنی در برابر این بارها، از روش تحلیل دینامیکی یک درجه آزادی برای تحلیل این نوع سازه و محاسبه خیز آن استفاده‌شده است. بارگذاری انفجار به‌صورت نمایی و رفتار سازه بتنی به‌صورت کشسان خمیری معادل به‌کاررفته است. سپس با استفاده از دو پارامتر مدت‌زمان تداوم بارگذاری و زمان رسیدن به انتهای ناحیه کشسان جهت تعیین محدوده پاسخ­‌ها، حالت­های مختلفی برای محاسبه معادله پاسخ و تعیین خیز حداکثر تیر بتنی در نظر گرفته‌شده است. با تحلیل تئوریک SDOF معادلات حرکت محدوده­‌های مشخص‌‌شده، در نهایت پاسخ‌­های پارامتریک تیرهای بتنی در برابر بار انفجار به دست آمد. با مقایسه خروجی این روابط با نتایج تست‌های آزمایشگاهی، مدل اجزا محدود و روابط دستورالعمل UFC 3-340-02، از دقت روش پیشنهادی اطمینان حاصل‌شده است. با انجام تحلیل­های مختلف در شرایط مختلف بارگذاری و خصوصیات مختلف سازه­ای، مشخص شد که دقت روش پیشنهادی در محاسبه خیز تیرها، بالای 90% است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Parametric Analysis of Reinforced Concrete Beams Under Blast Load

نویسندگان [English]

  • Seied Ahmad Hosseini 1
  • mohammad hasan Najafi Alamuti 2
1 Malek Ashtar University of Technology
2 Malek Ashtar University of Technology- Iran
چکیده [English]

In order to resolve long analysis and designing process and providing an easy and accessible method for calculating the response of concrete beams to explosion load, the dynamic analysis method for one degree of freedom system has been used to analyze this type of structure and its deflection. The explosive load is used exponentially and the behavior of the concrete structure is considered as elasto-plastic equivalent. Then, using two parameters of load duration and time to reach the end of the elastic region to determine the range of responses, different modes have been considered to calculate the response equation and determine the maximum deflection of the concrete beam by theoretical analysis of SDOF equations of motion for the specified ranges, and finally the parametric responses of concrete beams to the explosion load were obtained. By comparing the output of these relationships with the results of laboratory tests, the finite element model and the relationships of the UFC 3-340-02, the accuracy of the proposed method is ensured. By performing different analysis under different loading condition and different structural properties, it was found that the accuracy of the proposed method is above 90%.
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کلیدواژه‌ها [English]

  • Beam
  • Reinforced Concrete
  • Blast
  • Deflection
  • Single Degree of Freedom
  • UFC 3-340-02

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