9、含 NFRP 层板的振动分析

含 NFRP 层板的振动分析

1. 应力 - 应变关系与刚度系数

NFRP 层的应力 - 应变关系可表示为：
[
\begin{bmatrix}
\sigma_{11} \
\sigma_{22} \
\sigma_{33} \
\sigma_{23} \
\sigma_{13} \
\sigma_{12}
\end{bmatrix}
=
\begin{bmatrix}
Q_{11} & Q_{12} & Q_{13} & 0 & 0 & 0 \
Q_{12} & Q_{22} & Q_{23} & 0 & 0 & 0 \
Q_{13} & Q_{23} & Q_{33} & 0 & 0 & 0 \
0 & 0 & 0 & Q_{44} & 0 & 0 \
0 & 0 & 0 & 0 & Q_{55} & 0 \
0 & 0 & 0 & 0 & 0 & Q_{66}
\end{bmatrix}
\begin{bmatrix}
\varepsilon_{11} \
\varepsilon_{22} \
\varepsilon_{33} \
\gamma_{23} \
\gamma_{13} \
\gamma_{12}
\end{b