Simulation of tensile test

Hello :)

We are trying to make an simulation of a tensile test of a fiber compsite.

umaxa=163
umaxb=167

n=10000
area=0.064

rng('shuffle')
Umax=umaxa + (umaxb-umaxa).*randn(n,1);

for F=1:10000 
    K1(F,1)=(F*50)/(n*area);
end   
    while K1(F,1) < Umax(:,1)
        
        onoff = K1(F,1) < Umax(n,1);
        nny = sum(onoff,1);
        nn = n-nny;
        K1(F,1)=(F*10)/(nn*area);
        
    end
end

We are using randn to define maximum tensile strenght for each fiber, n is the amount of fibers.

We want to step on the force from 1 to 10000, so when the force increase on each fiber the tensile strenght is increasing.

Each fiber is getting evulated if their tensile strenght excess the maximum tensile strenght, if there is no fiber which breaks the force is being increased by the for loop.

If there is a fiber which excess the maximum tensile strenght it needs to be removed and the while loop shall calculate how many fibers which should be removed.

When there is a fiber removed we need to run the while loop again because of the tensile strenght is increased untill there is no more fiber getting removed at the value of the force. So the For loop can increase the force again and it runs all over. Untill there is zero fibers left.

The code above is our attempt to write it, but we cant manage to remove the amount of fibers and with this code it gets a K1 vektor with inf entries because the n value will reach below zero.

Answer 1

[darova]

An example

clc,clear

% umaxa=163;
umaxa=113;
umaxb=167;
n = 20;
area=0.064;
rng('shuffle')
Umax=umaxa + (umaxb-umaxa).*rand(n,1);
nn = n;
cm = jet(100);                        % colormap
F = 1;                                % start force
while (nn > 0) && (F < 10000)
    stress = (F*50)/(nn*area);        % stress of each fiber
    on = stress < Umax;               % fibers remain
    nn = sum(on);                     % actual number of fibres
%     F = F + 1;
    F = F + nn/n/10;
    cla
    title(sprintf('Stress = %0.2f',stress))
    hold on
    for i = 1:n
        if on(i)                                    % if fiber exists
            ind = round(100*stress/Umax(i));        % color index
            plot([i i],[0 n],'color',cm(ind,:))     % plot fiber
            str = sprintf('Umax = %0.0f',Umax(i));  % label
            text(i,n/2,str,'ROtation',90)           % plot label
        end
    end
    hold off
    pause(1)
end