단순지지 변단면보의 고유진동수 산정

Natural Frequencies of Simply Supported Tapered Beams

The finite element method was adopted to find out the natural frequencies of a sinusoidally tapered beam with simply supported boundary conditions. The parameters considered in the numerical analysis are the taper parameter, $\alpha$ ($\alpha$=0.0, 0.1, ~ , 2.0) and the sectional property parameters, m and n [(m, n):(0, 2), (1, 3), (2, 4)]. It is generally known that the results of the numerical analysis corresponding to each pair of sectional property parameters, (m, n) are represented by second order polynominals of $\alpha$ . The coefficients of a in the polynominals are determined by using the regression technique, which reveals small m in most cases of given sectional property parameters (m, n).