The potential pozzolanic activity of glass and red-clay ceramic waste as cement mortars components

The objective of this experimental study was to examine the possibility of reusing ceramic materials waste from container glass, bricks and tiles of red-clay ceramic industry in Portugal as partial cement replacement in mortar and concrete. The different types of waste were finely ground to specific sizes (0–45 μm, 45–75 μm and 75–150 μm) and its pozzolanic activity was determined. The reduction of glass and ceramic waste particle size was accomplished in the laboratory by crushing and grinding using a ball jar mill. After gridding, the fine waste materials were characterized by the determination of density, Blaine fineness and particle morphology using scanning electrical microscope. The compressive strength activity index, at 7, 28 and 90 days, was determined in mortars produced with each finely grounded waste ceramics and different percentages of partial cement replacement. Standard ASTM accelerated mortar bar tests and a modified test carried on in 40 × 40 × 160 mm size mortar specimens were performed to investigate the potential expansion caused by the alkali–silica reaction of finely grounded waste glass as partially cement replacement.The results obtained confirm the pozzolanic activity of the grounded waste, collected in the central region of Portugal, making feasible their incorporation as cement mortars and concrete components.

► The ceramic materials waste as partial cement replacement in mortar was examined.
► Different types and particles sizes of waste were incorporated in mortars.
► Compressive strength activity index of ground ceramics waste was determined.
► The ARS of glass fine waste was not detrimental to the mortars behaviour.
► Pozzolanic activity was obtained with a maximum particles sizes 45–75 μm.