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Shear Stress in Beams

Example: * The simply supported, 6 foot beam, AB, is acted on by a uniformly distributed load

(including the weight of the beam) of 1800 lb/ft. The x-section of the beam is 8 inches wide and

10 inches deep as shown below. Find the shear and bending stresses at a section 1.5 ft to the right

of end A at locations starting at the top and proceeding down in ¼ increments to the bottom fiber
as shown in the figure below. Show the stresses acting on each element.

Strategy: From the previous problem the shear at the section is 2700 lb as shown below.

Next show the elements at each location (1, 2, 3, 4, 5) for which the shear stress is to be calculated.

See the figure below.

Note: The shear stress at locations 1 and 5 is zero. There is no horizontal shear force on the beam.

Also the shear stress is symmetric about the neutral axis. So the shear stress at location 2 and 4

are the same. The maximum shear stress is at location 3 on the neutral axis.

Click here to continue with this example.

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