Modal Decoupling Using the Method of Weighted Residuals for the Nonlinear Elastic Dynamics of a Clamped Laminated Composite

Table 2

Modal parameters of the Duffing equation.

Mode	Natural frequency 𝜔𝑚𝑛,[(𝑠)^−1]	Natural frequency ratio	Stiffness 𝑟𝑚𝑛,[(𝑚𝑚⋅𝑠)^−2]
M1: 𝑚=1, 𝑛=1	6.7839𝑒3		7.1888𝑒6
M2: 𝑚=1, 𝑛=3	2.5381𝑒4	𝜔31/𝜔11=2.68	1.2548𝑒8
M3: 𝑚=3, 𝑛=1	4.2430𝑒4	𝜔31/𝜔13=1.68	4.3085𝑒8
M4. m=3, 𝑛=3	6.1008𝑒4	𝜔33/𝜔31=1.45	5.8140𝑒8