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Mlt represents the maximum moment caused by sidesway.

If purlins are placed at the joints of a truss top chord, the top chord is considered a beam-column.

A W14x74 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 1.06, and the multiplier to account for P-Δ effects was determined to be 1.25. Determine the required second-order axial strength, Pr, of the member.Type of analysisPu (kip)Mtop (kip-ft)Mbottom (kip-ft)Nonsway4454526Sway1004095 

A W14x82 of A992 steel is to be investigated for use as a beam-column in an unbraced frame. The length is 15 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 1.26. Determine the required second-order axial strength, Pr, of the member.Type of analysisPu (kip)Mtop (kip-ft)Mbottom (kip-ft)Nonsway4903532Sway1454095 

An unbraced beam-column within a rigid frame has an Euler buckling strength of 1,799 kips with a story shear of 4.43 kips. What is the drift index for the column?

Use the Steel Construction Manual to determine the plastic moment capacity, Mp, of a W18x106 beam made of A913 Grade 60 steel.

A W14x74 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 1.25. Determine the required second-order axial strength, Pr, of the member.Type of analysisPu (kip)Mtop (kip-ft)Mbottom (kip-ft)Nonsway3905017Sway1454090 

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

An engineer analyzes an unbraced frame and determines the sum of the required load capacities for all the columns in the frame is 487 kips (unfactored) while the total elastic buckling strength of the same frame is 3,492 kips. From these values, what is the ASD amplification factor for sidesway moments of the frame?

An engineer analyzes an unbraced frame and determines the sum of the required load capacities for all the columns in the frame is 225 kips (unfactored) while the total elastic buckling strength of the same frame is 4,249 kips. From these values, what is the LRFD amplification factor for sidesway moments of the frame?