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Sigma-theta, the bending stress, is a function of r only as expected from theory. It is tensile (positive) in the top part of the beam and compressive (negative) in the bottom part. There is a neutral surface that delineates the tensile and compressive regions. Sigma-theta is zero on the neutral surface. We will use probe to locate the region where the bending stress changes from tensile to compressive. In order to find the neutral axis, lets first enlarge the geometry. Do this by clicking the Box Zoom tool then click a drag a rectangle around the area you want to magnify. Now, click the probe tool in the menu bar This will allow you to hover the cursor over the geometry at see the stress at that point. Hover the cursor over the geometry until you have a good understanding where the neutral axis on the beam is. To zoom out, click "Zoom to Fit"

We will next now look at Sigma-theta along the symmetry line. Click Solution > Sigma-theta along symmetry in the outline window to bring up the stress distribution at the middle of the bar.

If they are not on, make sure to click on the max and min tags once again Look at the color bar to see the maximum and minimum stresses. The maximum theta-stress is 1697.63 psi and the minimum theta-stress is -1916.2 psi.

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Looking at the distribution, we can see that the stress varies only as a function of r as expected. Also, we can see that there is a stress concentration in the area where the moment is applied. In the theory, this effect is ignored. In order to further examine the Sigma-r, let's look at the variation along the symmetry line. Click on Solution > Sigma-r along symmetry. This solution is the normal stress in the r-direction at the midsection of the beam.

Click the Max and Min Tags in the menu bar: Image Removed they will show the maximum and minimum stresses and their locations. NowLooking at the color bar again, we can see that the maximum r-stress is -.110 psi, and the minimum r-stress is -82.302 psi.

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