Concrete is the most widely used building material in the world and consequently is being continuously developed to fulfill modern-day requirements.

Efforts to improve concrete strength have led to reports of porosity-free concrete (PFC), the hardest concrete tested to date.Some of the basic properties of PFC have already been explored, and now a team including Kanazawa University has probed the impact response of this innovative material. Their findings are published in International Journal of Civil Engineering.

The way in which PFC is prepared leads to very few voids in the final material, which gives it its high strength—400 MPa can be applied to PFC before it fails, compared with 20-30 MPa for standard concrete.Some of the basic material properties of steel fiber-reinforced PFC have already been reported; now the researchers have evaluated the impact response of a range of PFC preparations with different steel fiber contents and section heights.