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In the equation , the variable α is equal to _____ for LRFD.

A W14x74 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. Bending is around the strong axis. The effective length factors are Kx = 1.0 for the braced case, Kx = 1.0 for the unbraced case, and Ky = 1.0. 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 1.16. Using LRFD and Cb = 1.0, determine the value of the AISC interaction equation.Type of analysisPu (kips)Mtop (kip-ft)Mbottom (kip-ft)Nonsway3703026Sway552590 

In regard to trusses, purlins placed between the joints of the top chord would switch the top chord from being modeled as an axial-loaded compression member to a beam-column.

The beam-column of A992 steel is part of a braced frame with L = 15 ft, Pu = 300 kip, Mux = 125 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 equationW12x580.956W12x720.700W12x790.634W12x870.571W12x960.513 

A W8x31 beam made from A36 steel would be classified as _______.

An example of beam-columns can sometimes be found in roof trusses when purlins are placed between joints.

Using ASD, determine whether the following member satisfies the appropriate AISC interaction equation. Do not consider moment amplification. The loads are 50% dead and 50% live load. Bending is about the x-axis.Given:    W14x82, A992    Applied axial compression force = 220 kip    Applied constant bending moment = 180 ft-kip    L = 14 ft    pin-pin connected    laterally braced at ends    Kx = Ky = 1    Cb = 1

A W10x88 made of A572 Grade 42 steel is subjected to a maximum bending moment of 190 kip-ft about its x-axis. Determine the maximum magnitude of bending stress in the beam.

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.