Design and characterization according to EN14488 of a sprayed concrete mixture for a residual strength class.

This thesis presents a detailed experimental analysis of Fibre Reinforced Concrete (FRC), with particular emphasis on evaluating its mechanical behavior under different loading conditions. The study is structured in two experimental stages: the first one involves an examination of Steel Fibre Reinforced Concrete (SFRC), and the second focuses on Steel Fibre Reinforced Sprayed Concrete (SFRSC), which has recently proven to be a highly advantageous variant for challenging construction environments. The experimental campaign includes a comprehensive array of tests, such as the elastic modulus test, compression test, three-point bending test (3PBT), Barcelona test, and the EN 14488 - Method B. Each of these tests is designed to probe different aspects of the concrete’s behavior, providing insights into its structural integrity. The thesis also investigates the distribution of fibres within the concrete matrix, which is critical for its mechanical performance, using innovative methods like the inductive test and direct counting of fibres on cracked surfaces. In the second set of analyses, a comparison between the two casting methods is conducted to identify differences in mechanical properties, potentially attributable to fibre distribution and the rebound effect during spraying. The data reveal that SFRSC exhibits a reduction in some mechanical properties compared to SFRC, underscoring the need for careful application and processing techniques in spray deployment. This research contributes to the broader understanding of FRC materials, offering valuable data for improving construction techniques and optimizing fibre-reinforced concrete formulations. The findings highlight the importance of considering the distribution of the fibres in design and application to maximize the material’s mechanical properties and structural benefits.