A 22.2 mm diameter bolt having a diameter at the root of the threads of 18.6 mm is used to fasten two timbers as shown. The nut is tightened to cause a tensile load in the bolt of 34 kN. (a) Determine the shearing stress in the head of the bolt. (DRAW THE FREE BODY DIAGRAM) (b) Determine the shearing stress in the threads. (c) Determine the outside diameter of the washers if their inside diameter is 28 mm and the bearing stress is limited to 6 MPa. (DRAW THE FREE BODY DIAGRAM)

A 50' length of steel rail is laid on a day when the temperature is 30 °F. In order to prevent the rail from developing any internal stresses due to a thermal increase of 50 °F, what is the amount of deformation that needs to be accommodated with respect to the slotted connection at the rail end(s)? Steel rail L=60' Slotted hole Coeff. of Mod. of Mod. of Tensile Yield Thermal Ultimate Strength Expansion a in/in./F" x 10 Elasticity Rigidity G Strength Poisson's ksi Density pcf Ratio Material ksi ksi ksi Tens. Comp. Shear Steel ASTM A36 or 490 30,000 12,000 36 58 6.5 0.25 A501 Steel (high-strength low-alky) ASTM A992 490 30,000 12,000 50 65 6.5 0.25 Steel AISI 1020 490 30,000 11,500 30 55 6.5 0.25 hot-rolled Steel AISI 1040 490 30,000 11.500 42 76 6.5 0.25 hot-rolled Stainless steel (annealed) 490 29,000 11,600 40 85 60 6.5 0.25 Cast iron (gray) 490 15,000 6000 20 80 32 5.9 0.26 Aluminum allay 6061.16 165 10,000 4000 35 38 27 13.1 0.3 51-T6 Thanium alloy 275 16,500 6500 130 140 100 5.4…

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2. The clamp of the given figure is used to hold a cover in place. The screw of the clamp has a single thread with a mean radius of 0.20 in and a pitch of 0.08 in. The coefficient of friction is 0.45, and the required clamping force is 100 lb. (a) Determine the twisting moment to tighten the clamp and (b) determine the twisting moment to loosen the clamp.