What's a stress contour?

A stress contour uses color to show where the structure feels the forces, or stresses. In the case of the concrete dam simulation, the worst stresses are blues, then greens are a little better, and reds are the least nasty.

Your results from Franc are five stress contours.

Here is a series of stress contours for the simple gravity dam:

 Frame 0: the crack tip on the left side of the dam is surrounded by a small dark green circle; the crack tip on the upper right is surrounded by some red.

 Frame 1: The mesh is superimposed on the stress contour. The left crack tip has grown to the right and is surrounded by a lighter green region; the upper right crack tip has not really moved much. The left crack is being pushed to grow by the water loading on the left edge.

 Frame 2: the left crack tip has again grown to the right and is surrounded by a blue region; the upper right crack tip has not really moved much, but there is a region of high stress developing near the start of that crack (a blue region).

 Frame 3: the left crack tip has again grown to the right and a little bit upwards and is surrounded by a green/blue region; the upper right crack hasn't really moved, but the stress has lessened from blue to green. This is because the lower crack is absorbing the stress.

 Frame 4: the lower left crack tip has again grown to the right and a little bit upwards and is surrounded by a lighter green region; the upper right crack hasn't really moved.

 Frame 5: the lower left crack has grown to the right and up once again, almost reaching the other side of the dam; it has relieved almost all the stresses in the dam, seen by the red color of the contour. The upper right crack still hasn't really moved.

The applet now show the stress contours on a deformed shape, also. The deformed shape is an exaggeration of how the dam moves in reaction to the forces.