tritrussk

(./tritrussk.m)

Function Synopsis

k = tritrussk(p1,p2,p3,t,mu,lambda)

Cross-Reference Information

dotp           ./dotp.m
tensor         ./tensor.m

Listing of function ./tritrussk.m

function k = tritrussk(p1,p2,p3,t,mu,lambda)

s1 = p2-p1;
s2 = p3-p1;

D = dotp(s1,s1)*dotp(s2,s2)-dotp(s1,s2)^2;
s1cars2 = tensor(s1,s2)-tensor(s2,s1);
g1 = column(dotp((tensor(s1,s2)-tensor(s2,s1)),s2)/D);
g2 = column(dotp(s1,(tensor(s1,s2)-tensor(s2,s1)))/D);

b1 = -g1-g2;
b2 = g1;
b3 = g2;

B = [b1;b2;b3];

k = (t*(mu+lambda))*tensor(B,B);

I = eye(3);
dof = 3;
  
for i = 1:dof:3*dof
    for j = 1:dof:3*dof
      k(i:(i+dof-1),j:(j+dof-1)) =  k(i:(i+dof-1),j:(j+dof-1)) +...
                 I*(t*mu*dotp(B(i:(i+dof-1)),B(j:(j+dof-1))));
    end;
end;