نویسندگان

دانشگاه اصفهان

چکیده

در این مقاله، ارتعاشات مجموعه‌ای از تیرهای تیموشنکوی موازی با اتصالات انعطاف‌پذیر میانی به تعداد دلخواه بررسی می‌شود. بار متحرک، یک خودرو است که توسط یک سیستم شش درجه آزادی دومحوره به‌صورت جرم- فنر- مستهلک ‌کننده در حرکتی صفحه‌ای مدل می‌شود. جهت حل، روش جدیدی ارائه می‌شود که به‌کمک تغییر متغیری خاص، معادلات دیفرانسیل درهم‌گیر جدا می‌شود؛ بدین‌ منظور، باید ماتریس‌های سختی به‌دست آمده برای هر ستون از اتصالات میانی، بردارهای ویژه یکه شده یکسان داشته باشند. سپس به‌روش ماتریس انتقال، فرکانس‌ها و شکل مودهای تیرها و با به‌کارگیری تئوری آنالیز مودال، پاسخ اجباری سیستم تعیین می‌شود. جابه‌جایی خودرو، تیرها و ممان خمشی به‌ازای سختی‌ها و سرعت‌های مختلف به‌دست می‌آید و در ‌نهایت اعتبار نتایج مورد سنجش قرار می‌گیرد.

کلیدواژه‌ها

عنوان مقاله [English]

Vibration of Elastically Connected Multiple Timoshenko Beams under a Moving Six Degrees of Freedom System

نویسندگان [English]

  • S. Foroozande
  • A.R. Ariaei

چکیده [English]

In this article, the vibration analysis of a set of parallel Timoshenko beams connected by intermediate flexible connections, with arbitrary numbers, is studied. The moving load is a vehicle, which is modeled by a two-axle six degrees of freedom system, as a mass-spring-damper system, in a plane motion. For the solution, a new method is proposed which uses a change of variables strategy to decouple the system of differential equations. For this purpose, the stiffness matrix obtained from each column of intermediate connections should have the same normalized eigenvectors. The displacements and the bending moments of the beams and the vehicle due to changes in the stiffness of connections and changes in speeds will be examined. Finally, the validity of the results are measured.

کلیدواژه‌ها [English]

  • Parallel Timoshenko beams
  • Intermediate flexible connections
  • Two-axle six degrees of freedom system
  • transfer matrix method
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