A simply supported beam 30 ft long is prestressed by a straight tendon that carries
an effective force of 233 kips. The rectangular beam is 10 in. wide and 20 in. deep
and the eccentricity of the prestressing force is 4 in.
A. Calculate the maximum mid-span service moment the beam can support for
the allowable stresses listed in the table below:
Compressive Stress (psi) Tensile Stress (psi)
B. Draw a neat sketch to indicate the location of the center of the compression
force and its distance from the tensile force. What conclusions can you draw?
C. Repeat parts A and B but for the maximum service moment but at a location
distant 25 in. from the support.