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DO NOT CONSIDER LIVE LOAD REDUCTION. DO NOT INTERPOLATE WHEN USING TABLE A-8.9. 1. [20 points] Wood beam design. a) Select the lightest section for a typical interior joist (beam) using dimension lumber. The uniformly-distributed loads are: D = 15 psf and L = 50 psf. Use Douglas Fir-Larch No.2. The joists are 16" o.c. (on-center) and span 10 feet. b) Check the selected joist for shear. Do not include the shear stress factor, CH. You may use the maximum shear force, V, from the shear diagram (it is not necessary to find the value of shear at a distance, d, from the face of support). Do not redesign if the joist is no good. c) Check the selected joist for live load deflection (Lx12 / 360 criteria). Do not redesign if the joist is no good. 2. [20 points] Steel beam design. Select the lightest W-shape (A-992 steel) for the beam shown below. Do NOT check for shear or deflection.  3. [20 points] Reinforced concrete slab design. For a slab with 7" total thickness (h) and a clear span of 15 feet, compute the required bar spacing using No.3 bars, based on negative moment only. Use moment values for continuous spans found in Table A-8.7. Use f'c = 3 ksi and fy = 60 ksi. Assume 1" cover measured from the centerline of rebars. The load consists of slab weight (@ 150 pcf) and a live load, L = 150 psf. Check that spacing does not exceed 18" or 3h. Round down spacing to the first 1/2" increment. It is not necessary to check deflection.  4. [20 points] Reinforced concrete T-beam design. a) For the cross-section shown, select two steel rebars for positive moment only. The design moment is given, and does not need to be computed: Mu = wuL2 / 16 = 47.6 ft-k = 571.5 in-k. The clear span of the T-beam = 15 feet; and the centerline spacing between beams = 6 feet. Use f'c = 3 ksi and fy = 60 ksi. Assume 3" cover measured from the centerline of rebars. Remember to compute the effective width of the T-beam. b) Check "bar fit" and show that actual steel ratio is between minimum and maximum values. It is not necessary to check deflection. 5. [20 points] Reinforced concrete shear. A shear diagram for a rectangular reinforced concrete beam with a clear span of 16 feet has been computed and is shown below, along with the beam's cross-sectional dimensions. Use f'c = 4 ksi and fy = 60 ksi. a) Calculate the maximum spacing, using No.3 stirrups; b) Calculate the location, measured from the beam centerline (point "A" in the diagram below), to the point where this maximum spacing begins.
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