Eqilibrium Condition的用法和样例：
例句
- The condition of equilibrium of the member requires that the pair of forces coming from the joints must be equal and opposite.
元件的平衡条件要求来自连接点的一对力必须大小相等，方向相反。 - The coupling matrix is given by the interface displacement compatibility condition and the interface force equilibrium condition.
组合矩阵由交界面位移连续条件和交界面力的平衡条件给出。
