Hardening characterisation of a non-proprietary and more eco-friendly UHPC

•Early age properties evolution of a non-proprietary and more eco-friendly UHPC/UHPFRC.•Isothermal calorimetry revealed that induction period ends at 3 h, and the rapid evolution of hydration heat occurs up to 9 h.•Autogenous shrinkage exhibited a strong increase, particularly in the first 6 h.•MOE revealed a strong evolution in the first 8 h and reaching 60 % of 28 days’ MOE.•EMM-ARM seems a powerful tool for evaluating stiffness-related properties from very early age of UHPC/UHPFRC.