27 lines
1.2 KiB
Matlab
27 lines
1.2 KiB
Matlab
function ke=ele_stiff_matrix(E_ID,Nodes,Elements,E,u,Width)
|
||
ENodes(:,1) = Elements(E_ID,:);
|
||
iN = size(ENodes,1);
|
||
ke = zeros(2*iN,2*iN);
|
||
D=[E/(1-u^2),u*E/(1-u^2),0;
|
||
u*E/(1-u^2),E/(1-u^2),0;
|
||
0,0,E/(2*(1+u))];
|
||
|
||
% 计算高斯积分点坐标
|
||
kesi_yita=[-1/sqrt(3),-1/sqrt(3);1/sqrt(3),-1/sqrt(3);1/sqrt(3),1/sqrt(3);-1/sqrt(3),1/sqrt(3)];
|
||
|
||
w=[1,1];ww=[w(1)*w(1),w(2)*w(1),w(1)*w(1),w(1)*w(2)];
|
||
% 高斯积分计算单元刚度矩阵
|
||
for i=1:4
|
||
kesi=kesi_yita(i,1);yita=kesi_yita(i,2); %鎻愬彇褰㈠嚱鏁板<E98F81>kesi锛堟垨yita锛夌殑鍋忓<E98D8B>鍊?
|
||
J = Jacobi(E_ID,kesi,yita,Elements,Nodes); % 雅可比矩阵
|
||
% J=Q4_J(kesi,yita,xy); %璁＄畻J鐭╅樀
|
||
A=1/det(J)*[ J(2,2),-J(1,2), 0, 0;
|
||
0, 0,-J(2,1), J(1,1);
|
||
-J(2,1), J(1,1), J(2,2),-J(1,2)]; %鏍规嵁J鐭╅樀璁＄畻A鐭╅樀
|
||
G=Q4_G(kesi,yita); %鏍规嵁鍋忓<E98D8B>鍊艰<E98D8A>绠桮鐭╅樀
|
||
B=A*G; %鏍规嵁A鍜孏璁＄畻搴斿彉鐭╅樀B锛堥珮鏂<E78FAE>Н鍒嗙偣澶勭殑搴斿彉鐭╅樀B锛?
|
||
|
||
ke=ke+ww(i)*B'*D*B*Width*det(J);
|
||
|
||
end
|
||
end |