Composite Programme ABBD Matrix Trouble

Hi guys,

I am trying to create ABBD matrices for this programme but I am having a lot of trouble in getting the thicknesses from the mid plane all into the one matrix so that I can index them from there and calculate the ABBD matrices

I anybody could provide me with the code or an answer I would be extremely greatful

Stephen

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clear all

%MatLab Programme by Stephen Trainor

%21/01/12

% PROGRAMME INPUTS%

%lay-up properties%

fibre_angle = [0 0 45 -45 -45 45 0 0];%angle of plies

thickness = [0.125 0.125 0.125 0.125 0.125 0.125 0.125 0.125];%ply thickness

material = [1 1 1 1 1 1 1 1];%material of ply %material properties%

El(1)=138*10^9; %pascals

Et(1)=10.4*10^9; %pascals

Glt(1)=4.84*10^9;%pascals vlt(1)=0.25;

%if other material properties, input as El(2), El(3)....etc

%Loading; input the predetermine stress OR strain

Sigma=[0;601927;6.01927];% Applied stress matrix

Eps=[0;0;0];% Applied strain matrix

Sigmastar=Sigma/thickness(1)%averaged laminate stresses

Epsstar=Eps/thickness(1); %averaged laminate strains

%Qstar Inputs%

x=2; %the fraction relating the number of times the angle is reoccurring

a=1; %fraction of first angle

b=0; %fraction of second angle

c=0; %fraction of third angle

d=1; %fraction if angle is 0

e=0; %fractin if angle is 90

%no more programme inputs

%%%%------------------------------------------------------------%%%%

                        %MAIN PROGRAMME%

%%%%------------------------------------------------------------%%%%

%calculating all parts of Q matrix

Q11 = El/(1-((vlt^2)*Et/El))

Q22 = Et/(1-((vlt^2)*Et/El))

Q12 = (vlt*Et)/(1-((vlt^2)*Et/El))

Q66 = Glt

Q=[Q11,Q12,0; Q12,Q22,0; 0,0,Q66];

%angles to radians%

fibre_radians=(3.14/180)*fibre_angle;

num=size(fibre_angle); %used in transformation loop

num=num(2); %number of plies in laminate

%creating equivalent laminate

hsize=size(thickness);

hisize=hsize(2);

h=zeros(1,hsize+1);

h=sum(thickness);

%Generate ABBD

A=zeros(3,3);

B=zeros(3,3);

D=zeros(3,3);

hh=zeros(1,hsize+1);

for ii=1:hsize+1;

hh(ii)=-(h-(ii-1)*thickness)+h/2;

end

for ii=1:3;

for jj=1:3;

for kk=1:nplies;

A(ii,jj)=A(ii,jj)+Qh(kk,ii,jj)*(hh(kk+1)-hh(kk));

B(ii,jj)=B(ii,jj)+(1/2)*Qh(kk,ii,jj)*(hh(kk+1)^2-hh(kk)^2);

D(ii,jj)=D(ii,jj)+(1/3)*Qh(kk,ii,jj)*(hh(kk+1)^3-hh(kk)^3);

end

end

end

Answer 1

[ahmad ramzan sokhaimi]

i have a problem to find local stresses for [0 60 30 -45]. can i have a complete coding for it?