Look at this picture http://myfiles.dyndns.org/pictures/stress.jpg The top and bottom bars do not bend at all. The setup is taken outside where the temperature is 70C colder then a force of 100kN is applied to the top. Find the stress in each of the 3 columns. The area of each aluminum piece is 20mm^2, the brass is 60mm^2. These areas refers to the area that is touching the top (and bottom) plates. I can find the stress in each bar caused by the temperature change but how do I add in the force applied to the top? The aluminum shrinks faster than the brass so the aluminum is in tension and the brass is in compression. When that force is applied to the top, it puts more stress on the brass and relieves stress in the aluminum... but how much?