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Cement-based materials suffer from low tensile strength and limited strain capacity. They are brittle and highly sensitive to cracking, and such characteristics are the cause of the main distresses that limit the sustainability of their applications. Laboratory findings showed that the use of rubber aggregates obtained by grinding end-of-life tyres was effective in reducing the tendency of concrete cracking. This paper focuses on validating these findings in actual field conditions. For this purpose, control and rubberised concretes were produced using an industrial concrete plant and then used for the construction of prototype pavements. In equivalent conditions of construction, including length, the monitoring of the field experiment over a period of more than one year showed that the pavement constructed using control concrete tended to crack more due to shrinkage than the pavement constructed using rubberised concrete. Such experimental findings show that the use of a concrete incorporating rubber aggregates from used tyres may be an appropriate solution for sustainability, for economy and for saving non-renewable natural resources. [ABSTRACT FROM AUTHOR]

The standard European building specifications, grouped in a nine-volume Eurocode, describe different approaches for determining the properties of commonly used building materials such as steel, aluminium, concrete, etc. The American Concrete Institute (ACI) also offers different reports concerning concrete structures (ACI 318R), lightweight concrete (ACI 213R) and the long-term mechanical behaviour (ACI 209R) of concrete. Those reports, used as building codes, are applicable when the properties and composition of the material respect various criteria. All those materials that do not meet the scope criteria of Eurocode 2 or ACI reports because of their composition, property values or application cannot be used in the design of structures with those building codes. Regarding cement-based materials, concretes and mortars whose compressive strength is lower than the minima might not be useful for structures; however, they present an interesting potential for applications such as infrastructure materials, slabs-on-ground, etc. When designing structures and infrastructures in those materials, the accuracy of any formula offered by those building codes should be checked before being used. This article compares experimental measurements and predictive formulas for the engineering properties (compressive and tensile strengths, modulus of elasticity). The results show that the addition of specific aggregates with low stiffness and strength modifies the relation between those engineering properties, thus reducing the accuracy of some of the predictive formulas suggested in ACI reports or Eurocodes. [ABSTRACT FROM AUTHOR]