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16/10/2554 0:26 น.

G:\Bai's Memory\Knowledge & Education\Ot...\LinearFrame.m

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clc clear all; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%% Theerapat Singprasert ID : 5270608721 %%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Input zone by User %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% E = 1; A = 1.855*10e6; I = 9.27*10e3; nelem = 2; nnode = 3; node_coord = [ 0 0; 12.936 0.386; 25.872 0]; connec = [ 1 2; 2 3]; P = [ 0 0 0 0 -20 0 0 0 0]; % Nodal Load bc = [ 1 1 1 0 0 0 1 1 1]; % essential BC ( 1 = restrained ) disp = [ 0 0 0 0 0 0 0 0 0]; % Initial displacement %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Processing zone (Linear analysis) %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ndof = nnode*3; ks = zeros(ndof,ndof); % Element Stiffness for e = 1: nelem ns = connec(e,1); ne = connec(e,2); x_ns=node_coord(ns,1); y_ns=node_coord(ns,2); x_ne=node_coord(ne,1); y_ne=node_coord(ne,2); L=sqrt((x_ne-x_ns)^2+(y_ne-y_ns)^2); k = [ E*A/L 0 0 -E*A/L 0 0; 0 12*E*I/L 6*E*I/L^2 0 -12*E*I/L 6*E*I/L^2; 0 6*E*I/L^2 4*E*I/L 0 -6*E*I/L^2 2*E*I/L; -E*A/L 0 0 E*A/L 0 0; 0 -12*E*I/L -6*E*I/L^2 0 12*E*I/L -6*E*I/L^2; 0 6*E*I/L^2 2*E*I/L 0 -6*E*I/L^2 4*E*I/L]; dx = x_ne-x_ns; dy = y_ne-y_ns; %%%%%%%%%%%%%%%%%%%%%%%% % Tranformation Matrix %

16/10/2554 0:26 น.

G:\Bai's Memory\Knowledge & Education\Ot...\LinearFrame.m

%%%%%%%%%%%%%%%%%%%%%%%% cos = dx/L; sin = dy/L; T = [

cos sin 0 0 0 0; -sin cos 0 0 0 0; 0 0 1 0 0 0; 0 0 0 cos sin 0; 0 0 0 -sin cos 0; 0 0 0 0 0 1];

kGlo = T' * k * T; %%%%%%%%%%%%%%%% % Assemble k % %%%%%%%%%%%%%%%% dvec = [(ns-1)*3+1 (ns-1)*3+2 (ns-1)*3+3 (ne-1)*3+1 (ne-1)*3+2 (ne-1)*3+3]; for i=1:6 for j=1:6 ks(dvec(i),dvec(j))=ks(dvec(i),dvec(j))+kGlo(i,j); end end end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Input Boundary Condition % %%%%%%%%%%%%%%%%%%%%%%%%%%%%% kstar = ks; for i=1 : ndof if ( bc(i)==1 ) kstar(:,i) = 0; kstar(i,:) = 0; kstar(i,i) = 1; end end %%%%%%%%%%%%%%%%%%%%%%%%% % Assemble Force Vector % %%%%%%%%%%%%%%%%%%%%%%%%% force = P; for i=1 : ndof if( bc(i)==1 ) force(i) = disp(i); for j=1 : ndof if( j~=i ) force(j) = force(j) - ks(j,i)*disp(i); end end end end

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16/10/2554 0:26 น.

G:\Bai's Memory\Knowledge & Education\Ot...\LinearFrame.m

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ug = kstar\force'; %%%%%%%%%%%%%%%%%%%%%%%%%% % Internal element force % %%%%%%%%%%%%%%%%%%%%%%%%%% for e=1 : nelem ns = connec(e,1); ne = connec(e,2); x_ns=node_coord(ns,1); y_ns=node_coord(ns,2); x_ne=node_coord(ne,1); y_ne=node_coord(ne,2); L=sqrt((x_ne-x_ns)^2+(y_ne-y_ns)^2); ug_elem = [ug((ns-1)*3+1) ug((ns-1)*3+2) ug((ns-1)*3+3) ug((ne-1)*3+1) ug((ne-1) *3+2) ug((ne-1)*3+3)]; % From destination vector k = [ E*A/L 0 0 -E*A/L 0 0; 0 12*E*I/L 6*E*I/L^2 0 -12*E*I/L 6*E*I/L^2; 0 6*E*I/L^2 4*E*I/L 0 -6*E*I/L^2 2*E*I/L; -E*A/L 0 0 E*A/L 0 0; 0 -12*E*I/L -6*E*I/L^2 0 12*E*I/L -6*E*I/L^2; 0 6*E*I/L^2 2*E*I/L 0 -6*E*I/L^2 4*E*I/L]; dx = x_ne-x_ns; dy = y_ne-y_ns; %%%%%%%%%%%%%%%%%%%%%%%% % Tranformation Matrix % %%%%%%%%%%%%%%%%%%%%%%%% cos = dx/L; sin = dy/L; T = [

cos sin 0 0 0 0; -sin cos 0 0 0 0; 0 0 1 0 0 0; 0 0 0 cos sin 0; 0 0 0 -sin cos 0; 0 0 0 0 0 1];

ul_elem = T*ug_elem'; force_elem = k*ul_elem; Test = T\force_elem; % Checked Balanced Force (for nonlinear) %%%%%%%%%%%%%%%%%% % Element Output % %%%%%%%%%%%%%%%%%% No_of_element = e; No_of_element force_elem

16/10/2554 0:26 น.

G:\Bai's Memory\Knowledge & Education\Ot...\LinearFrame.m

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end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%% % Global Output % %%%%%%%%%%%%%%%%% ug