骨架曲线的弯矩-曲率关系 2.短期荷载下的弯矩-曲率关糸 截面的平衡方程 Ecl es oe h 2 ∈ 截面中心线 OsA n ∑X=0 △4.+σ.A+0.A+N=0 ∑M=0,M+oa△421+ha)+可。A(ah二、骨架曲线的弯矩-曲率关系 2. 短期荷载下的弯矩-曲率关系 截面的平衡方程 as h/2- as  h h/2- as Zi as  As  sAs  s As 1 i n  c1  s    ci M s As  ci 截面中心线 b N  X ciAi s As s As N i n = + + + = = 0  0 1 , ' '    ) 0 2 ) ( 2 0, ( 1  ＝ =  = +  + − + − n i ci i i s s s s s s h a A a h M M  A Z  A 