Comparison between the performance of expansive SCC and expansive conventional concretes in different expansion and curing conditions

•Influence of curing and restraining conditions in expansive SCC was evaluated.•Concrete composition influences the reactivity of the expansive agents.•Type-K agent reactivity depends greater in curing conditions than type-G agent.•Restraining conditions affect the morphology and composition of expansive hydrates.•Limestone filler is advisable instead of fly ashes when designing expansive SCC. Present paper evaluates the performance of expansive conventional concretes and expansive SCC, their physic-mechanical and microstructural properties, and their uniaxial restraining expansion regime, under different both restraining and curing conditions. The obtained results indicate that restraining conditions influence compressive strength and porosity structure, as well as the morphology and the chemical composition of the resulting expansive hydrates (ettringite formed from type-K agent and portlandite formed from type-G agent). The curing conditions and the concrete composition also influence the reactivity of the expansive agents. The use of limestone filler is advisable instead of fly ashes when designing expansive SCC.