1. A beam cross-section is limited to the size shown below. Determine the required area of reinforcement for service load moments MD = 430 ft-kip and ML = 175 ft-kip. f’c = 4,000 psi and fy = 60 ksi. Note that the beam self weight is already included in the dead load moment. Assume that c = 0.6cb for the singly-reinforced part of the section (for your initial guess). Hint: first calculate the nominal moment resisted by the concrete section without compression steel. Check the strength only.
