limit state的用法和样例：
例句
- The limit state equations of main failure modes are formulated by the increment interval load method.
并提出用区间增量载荷法生成主要失效模式的极限状态方程。 - The limit states are divided into two groups, the ultimate limit states and the serviceability limit states, which in turn may be subdivided further.
极限状态可分为两类，最大极限状态和使用极限状态，可以依次细分下去。
