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• Studied utilization of low-reactive copper mine tailings (MT) to produce green geopolymer bricks. • Slag as a supplementary cementitious material can enhance the geopolymerization kinetics. • Low-reactive copper MT together with slag can be used to manufacture green bricks satisfying ASTM requirements. To achieve sustainable construction and respond to the ever increasing demand for construction materials, including bricks, it is in an urgent need to use innovative technologies, like geopolymerization, to produce green and sustainable construction materials. Therefore, this study investigates the utilization of low-reactive copper mine tailings (MT) with slag (SG) as a supplemental cementitious material to produce green bricks based on the geopolymerization technology. To this end, the effects of several parameters including NaOH molarity (10 and 15 M), Na 2 SiO 3 /NaOH ratio (0, 0.5, 1, 1.5, 2, 2.5, and 3), slag (SG) content (0, 10, and 20 wt% of MT + SG), forming pressure (0, 5, 10, 15, 20, and 30 MPa), water-to-solid ratio (0.12, 0.14, and 0.16), and curing temperature (60, 75, 90, 105, and 120 ℃) on the physical and mechanical performance of geopolymer brick specimens are investigated through unconfined compression and water absorption tests. In addition, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analyses are conducted to understand the changes in microstructure and phase composition after geopolymerization. The results show that using only MT does not lead to a durable geopolymer product because of the low leaching of Si and Al species from the MT. However, with the incorporation of SG as a supplementary cementitious material, geopolymer bricks that satisfy the ASTM requirements can be produced. [ABSTRACT FROM AUTHOR]

• MgO boards displayed comparable physical characteristics as traditional board types. • Gypsum/wood boards were more vulnerable to soak-dry and freeze-thaw than MgO boards. • MgO boards had similar resistance to soak-dry and freeze-thaw as fibre cement boards. • Mg oxysulphate boards were more sensitive to high humidity than Mg oxychloride boards. The use of sheeting materials within the construction industry is becoming increasingly common as building materials and the way they are used evolves. Recently, magnesium-based construction boards have received more attention as alternatives for traditional sheeting materials. This is due to some of their enhanced properties, particularly fire resistance and lower embodied carbon. However, the lack of standardised documentation has caused concern regarding their composition, performance and long-term behaviour. This paper evaluates some of the test methods commonly used when assessing the performance of construction boards. A comparison between relatively novel magnesium-based boards and traditional boards is also conducted. Physical, mechanical and durability properties are investigated. Magnesium-based boards can provide relatively good bending strength values and water absorption behaviour which is comparable with other board types. Findings also demonstrate good performance for magnesium-based boards when exposed to soak-dry and freeze-thaw cycles. They suffered relatively small changes in bending strength, similar to that of fibre cement boards and superior to that of gypsum plasterboards and wood-based boards. [ABSTRACT FROM AUTHOR]