An experimental methodology to assess the performance of steel fiber reinforced self compacting concrete (FRSCC)

The fibre dispersing ability represents a key distinctive feature of the fresh state performance of a Steel Fibre Reinforced Self Compacting Concrete (SFR-SCC) which has to be carefully assessed, also in the sight of its outcomes on the mechanical performance in the hardened state. In this paper, with reference to a typical SFR-SCC mix, different methods to evaluate the resistance to static and dynamic segregation of fibres have been discussed and their results cross analyzed also in order to address a comprehensive testing methodology and assessing its reliability. Results obtained with reference to fresh state performance will be correlated to the fracture toughness properties in the hardened state, measured on specimens cast according to the same procedure employed for fresh state tests. This will allow a thorough evaluation of the correlation among fresh state performance, fibre dispersion and mechanical properties in the hardened state, furthermore enriching the meaningfulness, in a design oriented perspective, of material acceptance tests for quality control in the fresh state. The responsiveness and robustness of the proposed test methodologies will be finally widely assessed with reference to expected tolerances in the dosage of the mix constituents (water, cement, superplasticizers) which are mainly responsible of the performance in the fresh state.