One end of a steel girder in a bridge is kept on rollers instead of fixing it in a pillar because in summer or in winter when there is rise or fall in temperature, the girder may expand or contract without affecting the pillar or bridge.
One end of a steel girder in a bridge is kept on rollers instead of fixing it in a pillar because in summer or in winter when there is rise or fall in temperature, the girder may expand or contract without affecting the pillar or bridge.