Freeze-thaw effect on the durability of binary cements containing activated coal-mining waste

•The starting coal waste presented aluminosilicate properties.•Once the waste had been activated, the presence of kaolinite was not identified.•The addition 20% ACW to the blended cement has an influence on the hydrated phases.•After 300 freeze/thaw cycles, the 20% ACW mortar presented a higher resistance.•After 300 freeze/thaw cycles, the 20% OPC present less surface microfissuring in the crystals. The present work contains an approach to the evaluation of binary cements prepared with a 20% substitution of coal-mining waste and their behaviour under a maximum of 300 freeze/thaw cycles. Mineralogical studies are conducted, as well as tests on mass variations, compressive strength, microporosity, the dynamic modulus of elasticity, and SEM morphologies. It is important to highlight that the partial replacement of cement by 20% of activated coal waste, does not affect the durability against freeze/thaw cycles, since they show a fairly similar tendency to the reference mortar under extreme temperature changes.