Rotary Inertia and Higher Modes Effect on the Dynamic Response of Timoshenko Beams on Two-Parameter Elastic Foundation

Abstract

This study investigates the dynamic response of the axially loaded Timoshenko beams on two-parameter foundation with generalized elastic end conditions. A simplified modal analysis procedure is presented for the vibration analysis by using the conventional separation of variables method. The effects of higher modes and rotary inertia on the dynamic response of the forced Timoshenko beam are highlighted. A numerical example is presented to compare the modal responses of bending moment and shear force of the beams on Winkler and Vlasov type foundations with and without the rotary inertia effect.  

Keywords

• Rotary inertia,higher modes effect,separation of variables method,two-parameter foundation

Rotary Inertia and Higher Modes Effect on the Dynamic Response of Timoshenko Beams on Two-Parameter Elastic Foundation

Abstract

This study investigates the dynamic response of the axially loaded Timoshenko beams on two-parameter foundation with generalized elastic end conditions. A simplified modal analysis procedure is presented for the vibration analysis by using the conventional separation of variables method. The effects of higher modes and rotary inertia on the dynamic response of the forced Timoshenko beam are highlighted. A numerical example is presented to compare the modal responses of bending moment and shear force of the beams on Winkler and Vlasov type foundations with and without the rotary inertia effect.  

Keywords

• Rotary inertia,higher modes effect,separation of variables method,two parameter-foundation

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