.The shaft shown in the figure is machined from AISI 1040 CD steel. The shaft rotates at 1600rpm and is supported in rolling bearings at A and B. The applied forces are F1 = 2500 Ibf andF2 = 1000 lbf. Determine the minimum fatigue factor of safety based on achieving infinite life.If infinite life is not predicted, estimate the number of cycles to failure. Also check for yielding.

2- A double-angle tension member, 2L 3 x 2 × 1/4 LLBB, of A36 steel is subjected to a dead load of 12 kips and a live load of 36 kips. It is connected to a gusset plate with 3/4-inch-diameter bolts through the long legs. Does this member have enough strength? Assume that Ae = 0.85An.

16. 6-19. Determine the LRFD design strength and the ASD allowable strength of the section shown if snug-tight bolts 3 ft on center are used to connect the A36angles. The two angles, 4x3x3/8, are oriented with the long legs back-to-back(2L4×3×3/8 LLBB) and separated by 3/8 in. The effective length, (Lc)x=(Lc)y=12 ft.

2. For the interval 10 3 <N< 10° cycles, develop an expression for the axial fatigue strength (S'fJaxial for the polished specimens of 4130 used to obtain the figure below. The ultimate strength is Sut = 125 kpsi and the endurance limit is (S'e)axial = 50 kpsi.

A PL x 6 tension member is welded to a gusset plate as shown in Figure P3.2-2. The steel has a yield stress F, = 50 ksi and an ultimate tensile stress F = 65 ksi. Assume that A, = A̟ and compute a. the design strength for LRFD b. the allowable strength for ASD

4-62. If the 50 mm diameter supporting rods are made from steel, determine the average normal stress developed in each rod when P = 450 kN. 4-63.If the supporting rods of equal diameter are made from A992 steel, determine the required diameter to the nearest 3.175 mm of each rod when P = 450 kN. The allowable normal stress of the steel is o allow = 170 MPa.

1- The tension member shown in Figure is a PL 1/2x 8 of A36 steel (Fy = 36 ksi and Fu =58ksi). The member is connected to a gusset plate with 11/8 inch-diameter bolts. It is subjected to the dead and live loads shown. Does this member have enough strength? Assume that Ae = An- Use LRFD.

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 45 ft-kips, and the maximum moment for the service live load is 63 ft-kips (these moments occur at the same location on the beam and can therefore be combined). a. If load and resistance factor design is used, determine the maximum factored bending moment (required moment strength). What is the con-trolling AISC load combination? b. What is the required nominal moment strength for a resistance factor O of 0.90? c. If allowable strength design is used, determine the required moment strength. What is the controlling AISC load combination? d. What is the required nominal moment strength for a safety factor N of 1.67?

The two-bay portal frame shown can be subjected to either of the following load systems: OA horizontal load of 2W at B and a vertical load of 3W at the centre of span CD (b) A horizontal load of 2W at B and a vertical load of 3W at the centre of spanВС. If the plastic moment of the beams is 1.5 Mp and that of the columns M, calculate the minimum value of W which would cause collapse of the structure.Sketch the bending moment diagram of the structure at collapse indicating significant values.

3.2-2 A PL 3/8 x 6 tension member is welded to a gusset plate as shown in Figure P3.2-2. The steel has a yield stress Fy = 50 ksi and an ultimate tensile stress Fu = 65 ksi. Assume that Ae = A̟g and compute a. the design strength for LRFD b. the allowable strength for ASD