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Which of the following corresponds to the variable B2?

Which of the following corresponds to the variable B1?

Compute the value of Cm for a beam-column in single-curvature bending with a moment of 150 kip-ft on one end and a moment of 600 kip-ft on the other end.

Compute the value of Cm for a beam-column with a moment of 510 kip-ft at the top and a moment of 120 kip-ft at the bottom.

An unbraced rigid frame depends on the transfer of moments at its joints for stability. For this reason, unbraced frames are frequently referred to as _______ frames.

Using LRFD, determine the value of the AISC interaction equation for a W8x58 made from ASTM A992. Let L = 16 ft, Kx = Ky = 1.0, and Cb = 1.0. The factored loads are Pnt = 281.2 kip, Mnt = 177.6 kip-ft, The member is part of a braced frame, bending is about the x axis, and the LRFD moment amplification factor has been determined to be B1 = 1.248.

Compute the LRFD elastic critical buckling strength, Pe1, for the W18x65 made from ASTM A992 steel with L = 16 ft, P = 200 kip, M = 200 kip-ft, and Kx = Ky = 1.0. Bending is about the x axis. The member is part of a braced frame, and the given service loads are 50% dead load and 50% live load. The frame analysis was performed consistent with the effective length method, so the flexural rigidity was unreduced.

In the AISC 360 equation Mr = B1Mnt + B2Mlt, the variable B2 is the amplification factor for the moments resulting from sidesway.

In members subjected to both axial load and bending, the presence of the primary moment produces secondary moments.

A W14x82 of A992 steel is to be investigated for use as a beam-column in an unbraced frame. The length is 14 feet. First-order analyses of the frame were performed for both the sway and nonsway cases. The factored loads and moments corresponding to one of the load combinations to be investigated are given for this member in the following table. The multiplier to account for P-δ effects was determined to be 1.05, and the multiplier to account for P-Δ effects was determined to be 1.30. Determine the required second-order axial strength, Pr, of the member.Type of analysisPu (kip)Mtop (kip-ft)Mbottom (kip-ft)Nonsway3355034Sway18045105