Dynamic loading of prestressed concrete beams

The paper describes experiments to compare the behaviour of prestressed, post-tensioned concrete beams under dynamic loading with that under static loading. The total loading time was reduced from 10 min for the static loading to 0·05 s for the dynamic. This change in the rate of loading produced significant increases in the cracking strength of the concrete and in the ultimate moment of the beam. It was found that under dynamic loading prestressed concrete considerably increased its capacity for sustaining elastic deformation and for absorbing energy by inelastic deformation.