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A flat roof is subject to the following uniformly distributed loads: a dead load of 32 psf (pounds per square foot of roof surface), a roof live load of 14 psf, a snow load of 16 psf, and a wind load of 22 psf downward. If LRFD is used, determine the factored load (required strength), Ru.

The following are either LRFD or ASD load combinations. Which one(s) are for ASD? Select all that apply.

A 3/8 in. x 6 in. plate must resist a service dead load of 29 kips and a service live load of 33 kips in tension. The plate is connected to a gusset with four 1 in. bolts. Standard sizing is used for the bolt holes. The steel is ASTM A572 Grade 42: Fy = 42 ksi, Fu = 60 ksi. Assume that Ae = An. Using LRFD, does the plate have enough strength?

The symbol Ω represents _______, while the symbol φ represents _______.

Nominal strength = Allowable strength / Safety factor

A steel member is labeled as a W18x50. The 50 indicates the _______ of the member.

For ASD, the safety factor for fracture is smaller than the safety factor for yielding.

A 3/4 in. x 5.0 in. plate is connected to a gusset with three 1/2 in. bolts. Standard sizing is used for the bolt holes. The steel is ASTM A572 Grade 60: Fy = 60 ksi, Fu = 75 ksi. Assume that Ae = An. Compute the design strength for LRFD.

A 0.67 in. x 12.0 in. plate is connected to a gusset with eight 3/4 in. bolts. Standard sizing is used for the bolt holes. What is the net area of the plate?

Which is larger—the net area or the gross area of a tension member with bolt holes?