225
A P P E N D I X B
Samples of MATLAB
®
Programs
B.1 THE H-L METHOD FOR EXAMPLE 2.6
% The H-L method for Example 2.6
% The Limit State function: g(ka,kc,se,d,fa)
% Input the distribution parameters mx-mean,
% sz-standard deviation
clear, % Clear the memory
mx=[0.905,0.774,24.7,1.25,8.5]; % The means
sx=[0.0543,0.1262,2.14,0.0125,1.2]; % The standard
% deviations
n=5; % Total four random variables
beta=0; % Set beta=0
% Pick an initial design point x0(i)
for i=1:n-1
x0(i)=mx(i); %Use the means for the first n-1 variable
end
% Use surface of the limit state function to calclaue the
% value for the last random variable
x0(n)=x0(1)*x0(2)*x0(3)*(61.5*(x0(4))^2-15.279)/78.290;
% Initial point in standard normal distribution space
for i=1:n
z0(i)=(x0(i)-mx(i))/sx(i);
end
% Start iterative process
for j=1:1000
% Calculate the reliability beat0
% The Tylor series coefficent
G0(1)=sx(1)*x0(2)*x0(3);
G0(2)=sx(2)*x0(1)*x0(3);
G0(3)=sx(3)*x0(1)*x0(2);