고체역학 (Beer) — Pure Bending: Problem 4.52

4.52 A concrete beam is reinforced by three steel rods placed as shown. The modulus of elasticity is \(3 \times 10^6\) psi for the concrete and \(29 \times 10^6\) psi for the steel. Using an allowable stress of 1350 psi for the concrete and 20 ksi for the steel, determine the largest allowable positive bending moment in the beam.