Problems:
1. Complete text problem 16.5 on page 588. Note: The numerical answer provided is not correct. It
should be 5,333 lb/in2.
2. Complete text problem 6.9 on page 317 with the following addition.
3. Given the building and the forces shown to the right, what is the maximum diaphragm shear in the
north-south direction?
Answer: V = 32,400 lb,
= 540 lb/ft.
4. For the roof diaphragm of problem 3, use the provided table from the Uniform Building Code to
specify a nail and framing schedule if the joists in the diaphragm are 2 in. nominal timbers.
Partial Answer: Any for a 2 in. minimum nominal width of the framing member with an allowable shear
of 540 lb/ft or greater for a blocked diaphragm.
5. Lateral stability is particularly important for steel shapes such as plate girders and wide flange
sections. Describe the reasoning for the concern and ways to prevent problems.
6. Select an economical ASTM A992 W-shape beam with a simple span of 40 feet. Limit the
member to a maximum nominal depth of 18 in. Limit the live load deflection to L/360. The
nominal loads are a uniform dead load of 1.2 kip/ft and a uniform live load of 1.1 kip/ft. The
beam is braced at the 3rd points. Use the Available Moment vs. Unbraced Length curves.
Partial Answer: ASD: Mmax = 460 k-ft, or LRFD: Mu = 640 k-ft, Ix(req'd) ≥ 1639 in4, W18 x ____
6.9
In addition, how far could it span
if it carried the same load, but was one span of a 3-span continuous beam?
Answer: 58.4 ft if simply supported.
