A bridge truss extends 100 m across a river (Fig. P12.69). The structure is free to slide

Question:

A bridge truss extends 100 m across a river (Fig. P12.69). The structure is free to slide horizontally to permit thermal expansion. The structural components are connected by pin joints, and the masses of the bars are small compared with the mass of a 1 500-kg car halfway between points A and C. Show that the weight of the car is in effect equally distributed between points A and C. Specify whether each structural component is under tension or compression and find the force in each.

A bridge truss extends 100 m across a river