Effect of Bed and Crack on the Natural Frequency for the Timoshenko Beam Using Finite Element Method
الموضوعات : فصلنامه شبیه سازی و تحلیل تکنولوژی های نوین در مهندسی مکانیک
افشین منوچهری فر
1
(استادیار، دانشکده مکانیک، دانشگاه آزاد اسلامی واحد خمینی‌شهر)
فرید ابطحی
2
(کارشناس ارشد مکانیک، دانشگاه آزاد اسلامی واحد خمینی‌شهر)
الکلمات المفتاحية: FEM, Timoshenko beam, Crack, Bed of Beam,
ملخص المقالة :
In this study, the natural frequencies and mode shapes of beams without cracks and cracked Timoshenko beams is calculated with different boundary conditions using finite element method. The energy method is used to solve the equations. Hardness and softness matrices for Timoshenko beam without crack are obtained by solving the potential and kinetic energy equations. Then for investigation of cracked condition, the cracked element stiffness matrix is used and the beam natural frequencies are obtained by entering the boundary conditions of the beam. After that the effect of bed is investigated by addition of it to the equations.
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]16[ چهارمحالیپور، ا.، نحوی، ح.، بررسی رفتار ارتعاشی تیرهای دارای ترک، دانشکده مکانیک، دانشگاه آزاد خمینی‌شهر، 1387.
