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LRFD stands for _______.

A beam is part of the framing system for the floor of an office building. The floor is subjected to both dead loads and live loads. The maximum moment caused by the service dead load is 39 ft-kips, and the maximum moment for the service live load is 51 ft-kips (these moments occur at the same location on the beam and can therefore be combined). If LRFD is used, what is the required nominal strength of the beam for a resistance factor φ of 0.65?

A 0.88 in. x 8.1 in. plate is connected to a gusset with six 1-1/4 in. bolts. Standard sizing is used for the bolt holes. What is the gross area of the plate?

A 0.64 in. x 6.6 in. plate is connected to a gusset with four 1-1/8 in. bolts. Standard sizing is used for the bolt holes. What is the net area of the plate?

Low-alloy steels have higher strength and lower ductility than plain carbon steels.

A column is loaded in compression as follows. Using LRFD, find the required nominal strength for a resistance factor φ = 0.65.Dead load: 19 kipsFloor live load: 5 kipsRoof rain load: 8 kipsRoof live load: 10 kips

For LRFD, the resistance factor for yielding is smaller than the resistance factor for fracture.

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?