A simply supported concrete beam (18 ft. long) of f = 8000 psi which is in an exterior location is reinforced with four No.8 bars and is required to carry an additional factored moment of 200 k-ft. Assuming the beam is safe in shear for such a strength increase, design the number of layers of CFRP wrap system required to provide the additional factored moment capacity of 200 k-ft. The dimensions of the beam section are shown in Figure 2. Properties of CFRP wrap system are thickness of one ply, t = 0.035 in.; ultimate tensile strength, fru = 80 ksi; rupture strain, Eu= 0.014 in./in.; Modulus of elasticity of FRP layer, E, 5750 ksi; =0.85 and assume any other data suitably, if necessary. (Hint: Assume a reasonable lever arm between 0.85 to 0.9 times effective depth of the beam for a tension failure and no need to reiterate the calculations for refining the neutral axis depth or the lever arm) Note: the entire additional moment capacity is to be provided by the wrap and do not include the moment capacity from steel bars. (16 points) b = 15" b = 15" D = 24" 4 #8 Steel Figure 2 d = 21" D=24" d=17" 4 #8 Steel Figure 3