نویسندگان
دانشکده فنی و مهندسی، دانشگاه محقق اردبیلی
چکیده
از آنجایی‌که جهت طراحی بهینه میراگرجرمی هماهنگ شده در سازه های غیرخطی تحت اثر زلزله روابط ریاضی مشخصی وجود ندارد؛ استفاده از روشهای بهینه سازی عددی در سال‌های اخیر رواج یافته است. در روشهای عددی، بهینه سازی پارامترهای میراگر تحت اثر یک زلزله مشخص صورت می گیرد و با تغییر مشخصات زلزله ورودی، کارائی میراگر تغییر می کند. برای رفع این مشکل، در این مقاله با استفاده از روش الگوریتم ژنتیک و شبکه عصبی مصنوعی روش جدیدی ارائه گردیده که در آن اثرات هفت زلزله سازگار با شرایط زمین ساختی منطقه در بهینه سازی پارامترهای میراگر همزمان لحاظ می شود. روش پیشنهادی در یک سازه نمونه به‌کار رفته و نتایج حاکی از موفقیت آن در کاهش متوسط ماکزیمم پاسخ حاصل از هفت زلزله است.
کلیدواژه‌ها
عنوان مقاله [English]
Optimal Tuned Mass Damper for Nonlinear Structure under Different Earthquakes
نویسندگان [English]
- K. Shakeri
- M. Mohebbi
- G. Alizadeh
چکیده [English]
Since there is no closed-form formula for designing TMD (Tuned Mass Damper) for nonlinear structures, some researchers have proposed numerical optimization procedures such as a genetic algorithm to obtain the optimal values of TMD parameters for nonlinear structures. These methods are based on determining the optimal values of TMD parameters to minimize the maximum response (e.g. inter story drift) of the controlled structure subjected to a specific earthquake record. Therefore, the performance of TMD that has been designed using a specific record strongly depends on the characteristics of the earthquake record. By changing the characteristics of the input earthquake record, the efficiency of TMD is changed and in some cases, it is possible that the response of the controlled structure is increased. To overcome the shortcomings of the previous researches, in this paper, an efficient method for designing optimal TMD on nonlinear structures is proposed, in which the effect of different ground motion records is considered in the design procedure. In the proposed method, the optimal value of the TMD parameters are determined so that the average maximum response (e.g. inter story drift) resulting from different records in the controlled structure is minimized. To illustrate the procedure of the propose method, the method is used to design optimal TMD for a sample structure. The results of numerical simulations show that the average maximum response of controlled structure resulting from different records is reduced significantly. Hence, it can be concluded that the proposed method for designing optimal TMD under different earthquakes is effective.
کلیدواژه‌ها [English]
- Tuned Mass Damper (TMD)
- nonlinear dynamic analysis
- genetic algorithm
- optimization
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