In the present paper the governing dynamical equations for multilayered reinforced composite cylindrical shells based on Kirchhoff-Love's theory and Lekhnitsky's smeared stiffeners technique are derived. The shell is reinforced by longitudinal and ring stiffeners. | Vietnam Journal of Mechanics, VAST, Vol. 27, No. 4 (2005), pp. 220 - 228 DYNAMICAL ANALYSIS OF MULTILAYERED REINFORCED COMPOSITE CYLINDRICAL SHELLS DAO HUY BICH AND TRAN THANH TUAN Vietnam National University, Hanoi Abstract. In the present paper the governing dynamical equations for multilayered reinforced composite cylindrical shells based on Kirchhoff-Love 's theory and Lekhnitsky's smeared stiffeners technique are derived . The shell is reinforced by longitudinal and ring stiffeners. T he longitudinal stiffeners may be composite or sleeves with SMA wire. The linear problem of shell vibration is considered for illustrating the effects of the stiffeners, the shell geometry and altering t he lamination scheme on fundamental frequencies of the shell. 1. INTRODUCTION Unreinforced composite cylindrical shells has been analysed by analytical solution procedure or finite element technique [1-3 , 7, 9, 10, 12-16]. Many structures in the form of cylindrical composite shells reinforced by stiffeners are used in the aircraft industry, flight objects construction , ship industry and civil engineering . . . Static and buckling analyses of these structures have been investigated in [4 , 6, 11]. Dynamical analysis of them plays an important role in the anti-vibration practice. In this paper the motion equations of reinforced composite cylindrical shells are developed based on the Kirchhoff-Love 's theory and the Lekhnitsky's smeared stiffeners technique. The quantity analysis of the natural vibration problem of shells allows to discover the influence of stiffeners, the shell geometry and altering the laminat ion scheme on fundamental frequencies of the shells. 2. GOVERNING DYNAMICAL EQUATIONS Consider a symmetrically laminated multilayered composite cylindrical shell. The shell is reinforced by longitudinal and ring composite stiffeners. The longitudinal stiffeners may be sleeves with SMA wire and the sleeves are bonded on the shell surface . The wire is not bonded to the
