Question

3. (40 pts) Analyze the following statically determinate frame by hand and clearly draw the shear force, axial force, and bending moment diagrams indicating relevant (maximum and minimum) values for each of the following load cases: a) Uniform dead load (q) applied on the beam must add beam self-weight (concrete) to this value b) Uniform live load (qu) applied on the beam. c) Horizontal wind force (H H=12kip 12 x 20 gp-1.4 kip/ft -2.0 kip/ft 14 ft 12" x 12 12" x 12 25 ft 25 ft 4. (10 pts) Using the results from Problem 3, obtain the ultimate (design) moment to be used for the left end of the beam and the center of the beam using ACI 318-14 load combinations. For this problem, the combinations that apply are given below for reference (the equation numbers correspond to those found in ACI 318-14). Indicate what face of the beam is in tension for each combination at each of the two sections indicated U= 1.4 D U= 1.2 D+1.6 L U=1.2 D + 0.5 L+1.0W (5.3.1a) (5.3.1b) (5.3.1d)

Answer 1

Given that d_b = 1.4 kip/ft weight of concrete = 4 kip/ft^2 Total dead load = 1.4 kip/ft 4 times 12 times 20/(u) = 1.4 + 4 times 20/12 24.2/3 = 8.1 kip/ft R_A +R_D = 8.1 times 25 = 202.5 kip/ft H_A = 0 R_A times 25 = 8.1 times 25 times 25/2 R_D = 101.25 kip (b) lambda_L = 2 kip/ft R_A + R_D = 250 kip/ft H_A = 0 R_A + R_D = 125 kip H_A = 12 kip R_A times 25 + 12 times 14 = 0 R_A = 6.72 kip R_D = 6.72 kip}