The beam-column of A992 steel is part of a braced frame with L = 15 ft, Pu = 350 kip, Mux = 115 kip-ft. A second-order analysis was performed with factored loads and reduced member stiffnesses to obtain the moments and axial force. Bending is about the strong axis. Considering only the following shapes and values obtained from the AISC procedure for LRFD, select the lightest acceptable shape. Let Kx = 1.0, Ky = 1.0, and Cb = 1.0.ShapeValue of AISC interaction equationW12x581.020W12x720.744W12x790.675W12x870.608W12x960.547 

Unbraced frames are frequently referred to as _______ frames.

An engineer analyzes an unbraced frame and determines the sum of the required load capacities for all the columns in the frame is 464 kips (unfactored) while the total elastic buckling strength of the same frame is 2,325 kips. From these values, what is the ASD amplification factor for sidesway moments of the frame?

Drift index is the ratio of the story drift to the story width.

An unbraced beam-column with no moment frames has an Euler buckling strength of 2,158 kips with a story shear of 3.54 kips. What is the drift index for the column?

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 1.14, and the multiplier to account for P-Δ effects was determined to be 1.13. Determine the required second-order axial strength, Pr, of the member.Type of analysisPu (kip)Mtop (kip-ft)Mbottom (kip-ft)Nonsway4303018Sway1355090 

For small axial loads, the axial load term of the corresponding AISC interaction equation is slightly _______.

The factor Cm only applies to the _______.

In unbraced frames subject to sidesway, only one amplification factor is needed.

A W14x74 of A992 steel is to be investigated for use as a beam-column in an unbraced frame. The length is 13 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 1.17, and the multiplier to account for P-Δ effects was determined to be 1.21. Determine the required second-order axial strength, Pr, of the member.Type of analysisPu (kip)Mtop (kip-ft)Mbottom (kip-ft)Nonsway3504530Sway10555110