ABSTRACT
Most structural systems constructed today are made from reinforced, prestressed, or composite concrete having a wide range of characteristics and strengths. Structural concrete, whether normal weight or lightweight, is designed to have a compressive strength in excess of 3000 psi (20 MPa) in concrete structures. When the strength exceeds 6000 psi (42 MPa) such structures are defined today as highstrength concrete structures. Concrete mixtures designed to produce 6000 to 12,000 psi in compressive strength are easily obtainable today when silica fume or other pozzolans replace a portion of the cement content, resulting in lower water/cement (w/c) and water/cementitious materials (w/cm) ratios. Concretes
in the United States. These high-strength characteristics merit qualifying such concrete as super-highstrength concrete at this time.
