عنوان مقاله
بهینه سازی بازه ای پاسخ دینامیکی برای سازه هایی با پارامترهای بازه ای
فهرست مطالب
مقدمه
ماتریس های مشخصه بازه ای برای سازه هایی با پارامترهای بازه ای
تحلیل پاسخ دینامیکی سازه هایی با پارامترهای بازه ای
کاربرد در سازه تراس
کاربرد در سازه قاب بندی شده
نتیجه گیری
بخشی از مقاله
تحت این موقعیت ها، کلیه اطلاعات مربوط به پارامترهای سازه ای توسط تابع چگالی احتمال مشترک ( یا تابع توزیع) پارامترهای سازه ای فراهم می شود. متاسفانه، مدل احتمالی تنها راه برای تشریح عدم قطعیت نبوده و عدم قطعیت برابر با تصادفی بودن نیست. در واقع مدلهای احتمالی بدون داده های آزمایشی کافی برای اعتباریابی و ارزیابی فرضیات مطرح شده در مورد چگالی های احتمال مشترک متغیرهای تصادفی و توابع درگیر، توانایی ارائه نتایج معتبر و مطمئن با دقت مورد نیاز را ندارند.
کلمات کلیدی:
Interval optimization of dynamic response for structures with interval parameters Su Huan Chen *, Jie Wu Department of Mechanics, Nanling Campus, Jilin University, Changchun 130025, PR China Received 24 December 2002; accepted 2 September 2003 Abstract This paper presents an interval optimization method for the dynamic response of structures with interval parameters. The matrices of structures with interval parameters are given. Combining the interval extension of function with the perturbation theory of dynamic response, the method for interval dynamic response analysis is derived. The interval optimization problem is transformed into a corresponding deterministic one. Because the mean values and the uncertainties of the interval parameters can be elected as the design variables, more information of the optimization results can be obtained by the present method than that obtained by the deterministic one. The present method is implemented for a truss structure and a frame structure. The numerical results show that the method is effective. 2003 Elsevier Ltd. All rights reserved. Keywords: Interval optimization; Interval parameter structure; Interval parameter; Interval extension of function; Deterministic optimization; Interval dynamic response 1. Introduction The deterministic optimization [1,3–5,8] of structural behavior has been well developed for specified structural parameters and loading conditions. However, in most practical situations, the structural parameters and loads are uncertain, for example, there may be measurement inaccuracy or errors in the manufacturing process. Therefore, the concept of uncertainty plays an important role in the investigation of various engineering problems. The most common approach to problems of uncertainty is to model the structural parameters as random variables or fields. Under the circumstances, all information about the structural parameters is provided by the joint probability density function (or distribution function) of the structural parameters. Unfortunately, probabilistic model is not the only way one could describe the uncertainty, and uncertainty does not equal randomness. Indeed, probabilistic methods are not able to deliver reliable results at the required precision without sufficient experimental data to validate the assumptions made regarding the joint probability densities of the random variables or functions involved. Since the mid-1960s, a new method called the interval analysis has appeared. Moore [10] and his co-workers, Alefeld and Herzberger [2] have done the pioneering work. The linear interval equations and nonlinear interval equations have been resolved. Hansen [9] in his book discussed the global optimization using interval analysis. Because of the complexity of the interval algorithm, it is difficult to deal with practical engineering problems. Recently, the interval analysis method has been used to deal with the static displacement, eigenvalue, and dynamic response analysis of the uncertain structures with interval parameters [6,7,11]. However, few papers can be found about the optimization of structures with interval parameters in engineering. Hence, it is necessary to develop an effective method to solve the optimal problems of structures with interval
