A concrete beam of rectangular sections is 10 cm wide and is reinforced with steel bars whose axes are 30 cm below the top of the beam. Estimate the required total area of the
cross-section of the steel if the maximum compressive stress in the concrete is to be 7.5 MN/m2 and the tensile stress in the steel is 135 MN/m2 beam is subjected to pure
bending. What bending moment would the beam withstand when in this condition? Assume that Young's modulus for steel is 15 times that for concrete and that concrete can
sustain no tensile stresses. (Cambridge)