Effect of water/cement ratio on micro-nanomechanical properties of the interface between cementitious matrix and steel microfibers in ultra-high performance cementitious composites

abstract: Ultra-high performance concretes with steel microfibers have been studied in depth the aim of producing more efficient and durable structures. The these materials depends on characteristics interface between cementitious matrix. This research investigates micro-nanomechanical properties interfacial transition zone matrix ultra-high composite. effect water/cement ratio distance from microfiber were analyzed. results confirm formation high-density calcium-silicate-hydrate (HD C-S-H) at higher concentrations than low-density (LD for w/c ratios 0.2 0.3. very similar to that measured cement paste, no significant difference was observed regarding relation elastic modulus, hardness chemical composition. Thus, authors can conclude a less resistant region does not occur paste/microfibers.