课堂测试(7)
课堂测试（7） X1 X2 X4 MF X3 M1 M2 M3 M4
课堂测试(7)
课堂测试（7） X1 X2 TF X3 T1 T2 T3 T4
课堂测试(7 M,ME dx+[IF M.·M El Gl Gl M,Mdx≠0[元,rd=0△1≠0JM,M=07x=0=61=0 ∫M2Mdx=0∫2,Tdr=0△2=0 ∫.Mdx=0不,rdx=06 1,,Mdx=0「T7dx=06=6,=0 M,AMdx=0「,Tdx=0△=0 M,Mdx≠0∫T,dx=0a:=61≠0 JM.Mdx≠0j7,Tx=04≠0im2dx=0,=06=6=0 M2,Mdx=0「T;7dx=06=61=0 7 T
课堂测试（7） d d i F i F iF l l p M M T T x x EI GI = + d d i j i j ij l l p M M T T x x EI GI = + 1 2 M M x = d 0 1 d 0 M M x F M T 1 d 0 T T x F = 1 0 F 2 d 0 M M x F = 2 d 0 T T x F = 2 0 = F 3 d 0 M M x F = 3 d 0 T T x F = = 3F 0 1 2 T T x = d 0 12 21 = =0 1 3 M M x = d 0 1 3 T T x d =0 13 31 = =0 2 3 M M x = d 0 2 3 T T x = d 0 23 32 = =0 M1 M2 M4 MF T1 T2 T4 TF T3 M3 4 d 0 M M x F 4 d 0 T T x F = 4 0 F 1 4 M M x d 0 1 4 T T x d =0 14 41 = 0 2 4 TTx = d 0 24 42 = =0 3 4 M M x = d 0 3 4 T T x = d 0 34 43 = =0 2 4 M M x = d 0
课堂测试(7) M,ME dx+[IF M.·M El Gl Gl M,Mdx≠0[元,rd=0△1≠0JM,M=07x=0=61=0 ∫M2Mdx=0∫万 Tdx=0△2=0 T1·Tdx=0 Mdx=0「,7dx=0,=6=0 M,AMdx=0「,Tdx=0△=0 M,Mdx≠0∫T,dx=0a:=61≠0 「M4M≠07rd=0△≠0j2,Md=0j7d=061=8=0 JM. MAdr=0 JT, Tdx=0 =043=0 1X1+12x2+a3X3+4X4 1X1+14X4+△1F=0 1x1+52x2+62x3+a1x1+A2=0{x2=0 1X1+32X2+33+34X4+△3F=0 X2=0 641X1+6X4+△A=0 1X1+2X2+3X3+o4X4+△4F=0 x1≠0,X2=0,X3=0,X4≠0 对称结构的对称截面上的对称内力为0,反对称内力不为0 对称结构上作用了反对称载荷→二次超静定问题
31 1 32 2 33 3 34 4 3 X X X X + + + + = F 0 21 1 22 2 23 3 24 4 2 X X X X + + + + = F 0 11 1 12 2 13 3 14 4 1 + 0 X X X X + + + = F 33 3 X = 0 22 2 X = 0 11 1 14 4 1 0 X X + + = F 1 2 3 4 X X X X = = 0, 0, 0, 0 对称结构的对称截面上的对称内力为0，反对称内力不为0 对称结构上作用了反对称载荷 二次超静定问题 课堂测试（7） d d i F i F iF l l p M M T T x x EI GI = + d d i j i j ij l l p M M T T x x EI GI = + 1 2 M M x = d 0 1 d 0 M M x F 1 d 0 T T x F = 1 0 F 2 d 0 M M x F = 2 d 0 T T x F = 2 0 = F 3 d 0 M M x F = 3 d 0 T T x F = = 3F 0 1 2 T T x = d 0 12 21 = =0 1 3 M M x = d 0 1 3 T T x d =0 13 31 = =0 2 3 M M x = d 0 2 3 T T x = d 0 23 32 = =0 4 d 0 T T x F = 1 4 M M x d 0 1 4 T T x d =0 14 41 = 0 2 4 M M x = d 0 2 4 TTx = d 0 24 42 = =0 3 4 M M x = d 0 3 4 T T x = d 0 34 43 = =0 41 1 42 2 43 3 44 4 4 0 X X X X + + + + = F 41 1 44 4 4 + + 0 X X = F 4 d 0 M M x F 4 0 F
课堂测试(7) M TF 0.0≤x,≤L/2 x1,0≤x1≤L/2 ,0≤x≤L/2 Fx,0≤x2≤2L 1x2.0≤x2≤2L 1.0≤x≤2L T(x)=0 0,0≤x≤L/2 (x)={L 0≤x1≤L/2 0≤x,<2L T(x)=100≤x≤2L 2LFx,·x 2 dx=16Fz3 3E qx、4FL2 2L Fx
课堂测试（7） 3 2 2 2 1 0 16 2 d 3 L F Fx x FL x EI EI = − = − M T M1 M4 MF T1 T4 TF 1 2 2 0,0 / 2 ( ) ,0 2 F x L M x Fx x L = ( ) 0 T x F = 1 1 1 2 2 ,0 / 2 ( ) ,0 2 x x L M x x x L = 1 1 2 0,0 / 2 ( ) ,0 2 2 x L T x L x L = 1 4 2 0,0 / 2 ( ) 1,0 2 x L M x x L = 1 4 2 1,0 / 2 ( ) 0,0 2 x L T x x L = 2 2 2 4 0 4 2 d L F Fx FL x EI EI = =