20.3.1.1. Nominal Strength for Laterally Stable Compact Sections

Try these first

1. 1.

   What is the plastic moment strength (M_p) if Z = 20 in^3 and F_y = 30 ksi?

   Hint

   Use the formula M_p = Z * F_y.

2. 2.

   Define nominal strength in one sentence.

   Hint

   Think about the definition and the implications of strength.

3. 3.

   What is the formula for calculating nominal strength for stable compact sections?

   • A. M_n = ZF_y
   • B. M_n = F_y / Z
   • C. M_n = Z + F_y

   Hint

   Think about how both Z and F_y contribute to bending strength.

4. 4.

   True or False: A higher plastic section modulus increases the nominal strength of a beam.

   • True
   • False

   Hint

   Recall how Z relates to bending capacity.

5. 5.

   A steel beam has a plastic section modulus of 25 in^3 and is made from steel with a yield strength of 40 ksi. Calculate the nominal strength and discuss its application in a real-world situation.

   Hint

   Remember to multiply the plastic section modulus by the yield strength.

6. 6.

   Assuming a steel beam has a nominal strength of 1200 kip-in and a section modulus of 30 in^3. What is the yield strength? Provide reasoning.

   Hint

   Rearranging the nominal strength formula will help you find the yield strength.