% w_xxyy term coef = 2*Dxy/(dx^2 * dy^2); if i-1>=1 && j-1>=1, A_mat(idx, node(i-1,j-1)) = A_mat(idx, node(i-1,j-1)) + coef; end if i-1>=1, A_mat(idx, node(i-1,j)) = A_mat(idx, node(i-1,j)) -2*coef; end if i-1>=1 && j+1<=ny, A_mat(idx, node(i-1,j+1)) = A_mat(idx, node(i-1,j+1)) + coef; end if j-1>=1, A_mat(idx, node(i,j-1)) = A_mat(idx, node(i,j-1)) -2*coef; end A_mat(idx, idx) = A_mat(idx, idx) +4*coef; if j+1<=ny, A_mat(idx, node(i,j+1)) = A_mat(idx, node(i,j+1)) -2*coef; end if i+1<=nx && j-1>=1, A_mat(idx, node(i+1,j-1)) = A_mat(idx, node(i+1,j-1)) + coef; end if i+1<=nx, A_mat(idx, node(i+1,j)) = A_mat(idx, node(i+1,j)) -2*coef; end if i+1<=nx && j+1<=ny, A_mat(idx, node(i+1,j+1)) = A_mat(idx, node(i+1,j+1)) + coef; end end
The following MATLAB code performs a bending analysis of a composite plate using FSDT: Composite Plate Bending Analysis With Matlab Code
%% 8. Post-processing % Extract w at nodes W = zeros(nNodes,1); for i = 1:nNodes W(i) = U((i-1)*ndof + 1); end % w_xxyy term coef = 2*Dxy/(dx^2 * dy^2);
% Strain-displacement matrices % Membrane: Bm (3x8) Bm = zeros(3,8); for inod = 1:4 Bm(1, (inod-1)*2+1) = dN_dx(inod); Bm(2, (inod-1)*2+2) = dN_dy(inod); Bm(3, (inod-1)*2+1) = dN_dy(inod); Bm(3, (inod-1)*2+2) = dN_dx(inod); end =1 && j-1>
% Mesh Density nx = 20; % Elements in x ny = 20; % Elements in y