Evaluation of the mechanical behavior of concrete with recycled aggregate reinforced with steel fibers in order to obtain constitutive equations

Abstract

Materials such as concrete with recycled concrete aggregates (CRCA) are being studied due to the growing need to reduce the exploitation of natural resources and decrease the volume of concrete waste at its production site. However, recycled aggregates can result in a significant reduction in the compressive strength of CRCA due to its greater total porosity. The use of fibers can be an interesting strategy to enable the use of CRCA in certain applications. The use of fibers could provide a post-cracking strength which could turn CRCA suitable for structural applications where this parameter is critical. The use of fibers ensures that concretes have post-cracking strength, which can help to make CRCA feasible in applications where residual strength is the main parameter such as pavements. The parameterization of the behavior of concrete with recycled concrete aggregates with steel fibers (CRCASF), according to the recent criteria of design codes for structural purposes, has not yet been carried out. In this context, this experimental study proposes to characterize CRCASF with different percentages of substitution of natural aggregates for recycled ones and different levels of steel fibers through the DEWS test that allows obtaining constitutive equations and identifying the potential of this material for structural applications. The complementary characterization of the material will occur through tests of axial compression, modulus of elasticity, and specific mass. With these characterizations, parameters will be defined to assess the applicability of CRCASF for structural purposes.(AU)