It belongs to geometry invariable system and has the ability of undertaking the design load 结构是由不同的构件组成的几何不变体系，具有承担设计荷载的能力。
2.
2 ) quiet fixed and supper quiet fixed structure refer to the aspect of geometry composition and bearing load state , the quiet fixed structure is a geometry variable system that does not have redundant restrict . its all reverse force and inner force can be computed with quiet equilibrium equation and the relative result is uniqueness 2 ）静定结构与超静定结构静定结构是指在几何组成方面，它是无多余约束的几何不变体系；在受力状态方面，它的全部反力和内力均可由静力平衡方程所求得，且其解具唯性。
