linearstiffness.m

薄壁结构有限元计算

% 输入单元长度
l=input('Please input the length of the element: ');

% 输入单元层数
n=input('Please input the number of layers: ');

% 输入x向静矩、y向静矩、弹性模量、剪切模量、扭转常数、密度、固有频率
% Sx=input('Please input the x-direction of shear-moment of the section: ');
% Sy=input('Please input the y-direction of shear-moment of the section: ');
E=input('Please input the elastic modulus of the material: ');
mu=input('Please input the poisson ratio: ');G=0.5*E/(1+mu);
rho=input('Please input the density of the material: ');

w1 = E*A/l;
w2 = 12*E*Iy/(l*l*l);
w3 = 6*E*Iy/(l*l);
w4 = 4*E*Iy/l;
w5 = 2*E*Iy/l;
w6 = 12*E*Ix/(l*l*l);
w7 = 6*E*Ix/(l*l);
w8 = 4*E*Ix/l;
w9 = 2*E*Ix/l;
w10 = G*J/l;
Ke1 = [w1  0   0   0    0   0   -w1 0   0   0    0   0 ;
       0   w2  0   0    0   w3  0   -w2 0   0    0   w3 ;
       0   0   w6  0    -w7 0   0   0   -w6 0    -w7 0 ;
       0   0   0   w10  0   0   0   0   0   -w10 0   0 ;
       0   0   -w7 0    w8  0   0   0   w7  0    w9  0 ;
       0   w3  0   0    0   w4  0   -w3 0   0    0   w5 ;
       -w1 0   0   0    0   0   w1  0   0   0    0   0 ;
       0   -w2 0   0    0   -w3 0   w2  0   0    0   -w3 ;
       0   0   -w6 0    w7  0   0   0   w6  0    w7  0 ;
       0   0   0   -w10 0   0   0   0   0   w10  0   0 ;
       0   0   -w7 0    w9  0   0   0   w7  0    w8  0 ;
       0   w3  0   0    0   w5  0   -w3 0   0    0   w4];
Ke3=[Ke1(1:6,1:6)  zeros(6,1) Ke1(1:6,7:12)  zeros(6,1);
     zeros(1,6)    70*w4      zeros(1,6)     -60*w4;
     Ke1(7:12,1:6) zeros(6,1) Ke1(7:12,7:12) zeros(6,1);
     zeros(1,6)    -60*w4     zeros(1,6)     70*w4];