ABSTRACT
It must have been due to a surfeit of the ‘pioneering spirit’ for a small group of designers and concrete producers to have the will to launch highstrength concrete in the mid-1960s. Why innovate in concrete technology by increasing compressive strength? At that time, most designers were satisfied to design structures based on the 15 to 20 MPa concretes that were well understood, economical and safe. Similarly, concrete producers were making enough money by selling their concrete in ‘horizontal-type’ structures. It was not obvious to most engineers that concrete would one day displace steel in the construction of high-rise buildings. The conventional wisdom at that time was that concrete was only good for use in high-rise buildings for foundations and the construction of floors or to protect structural steel elements against fire.
