nLoops = 5; % number of times to loop
nElem = 18; % number of elements in each vector (let's use it as long as you know what it is
combinedResults = zeros(nElem,nLoops); % it's good practice to preallocate variables generated in a loop
for i = 1:nLoops
displacement = rand(nElem,1); % I don't have your data, so I'm using rand to simulate it
combinedResults(:,i) = displacement; % Here's where it sounds like you need help. The column you save to increments with i.
end
