Question: A three-axle truck crosses a 15-m simply supported span. The front and center axles are spaced 3 m apart and the center and rear axles are 4.2 m apart. The front axle carries 36 kN, the center 81 kN, and the rear 153 kN. Calculate the maximum bending moment as this truck rolls across the span from left to right and specify the axle positions for the maximum moment.