Steel reinforcement ·Internal moments in continuous composite beams can be determined by elastic analysis or, -Structural steel subject to certain section conditions,by rigid-plastic analysis 结构分析方法：弹性分析， 塑性极限分析 Negative moment Whether plastic analysis is (a)Both spans loaded appropriate depends on the susceptibility of the beam to local buckling: 0 塑性极限分析适用条件 Negative moment • Internal moments in continuous composite beams can be determined by elastic analysis or, subject to certain conditions, by rigid-plastic analysis. • 结构分析方法：弹性分析， 塑性极限分析 • Whether plastic analysis is appropriate depends on the susceptibility of the beam to local buckling： • 塑性极限分析适用条件