The composition and design of high-strength concrete and ultrahigh-strength concrete

Abstract The term “compressive strength” represents the value of strength measured during a compression test. Experience has shown that while most concrete properties represent average values, compressive strength represents instead an extreme value. The rupture of a concrete sample starts at its weakest link, and the concrete porosity plays a key role in determining the concrete compressive strength. But as it is not easy to measure concrete porosity, various indirect relationships linking concrete porosity to other concrete parameters that are easier to calculate and express have been proposed. For example, Feret’s and Abrams’ laws link concrete compressive strength to the value of the water to cement ratio. Usually, concrete mix design is calculated using the absolute volume method. This method is based on semiempirical relationships that enable the calculation of the volume of each concrete ingredient, and then the transformation of these volumes as kilograms per cubic meter.