20.3. Flexural Design

Try these first

1. 1.

   What defines a plastic hinge?

   Hint

   Think about where a beam might start to yield.

2. 2.

   What is the formula for nominal strength in a compact section?

   Hint

   Remember, it involves plastic section modulus and yield strength.

3. 3.

   What is the nominal moment strength formula for compact sections?

   • M_n = Z * F_y
   • M_n = F_y / Z
   • M_n = Z + F_y

   Hint

   Remember the components involved in the equation.

4. 4.

   True or False: All sections can be classified as either compact or partially compact.

   • True
   • False

   Hint

   Think about how beam categories help in design.

5. 5.

   A steel beam is designed with a width of 12 inches and a thickness of 0.5 inches. Determine if it qualifies as compact based on the width-to-thickness ratio for flanges.

   Hint

   Always reference the given formulas for critical ratios.

6. 6.

   A beam experiences a load causing a moment of 5000 in-lbs. Calculate the necessary plastic section modulus given that the yield strength is 36 ksi.

   Hint

   Use units correctly to ensure accurate calculations.