Performance of aluminium shaving waste and silica fume blended mortar

This study investigates the impact of aluminium shaving waste (ASW or A_x: 0.0, 1.0, 1.5, 2 wt%) on the silica fume (SF or S_y: 0-10 %) blended ordinary Portland cement (OPC or C_88-100%) mortar. The sample was designated as C_100-x-yS_yA_x and the evaluations were done through their performances in terms of workability, compressive strength, thermal residual strength and microstructural characteristics in comparison with the OPC only mortar (C₁₀₀S₀A₀). The increase in ASW/SF ratio enhanced the workability of SF blended (C_90-xS₁₀A_x). The unit weight of mortar reduced with increase in ASW/SF ratio so that 19.7 % was lost with the incorporation of 2 % of ASW. ASW induced effervescence of hydrogen gas in the fresh sample thereby leading to unit-weight reduction. The inclusion of 1 % ASW in ternary blending gave the optimum performances of 28-day strength (53.8 MPa) and residual thermal (300 °C, 1 h) strength of 56 MPa that had a comparable value to OPC mortar (55 MPa) unexposed to the thermal treatment. ASW also caused thermal stability in SF-ASW blended mortar as addition of 0.5, 1.5 and 2 % ASW caused 33.8, 15.6 and 33.4 % loss in 28-day strengths, respectively, while the least was observed in 1 % ASW sample with the loss of 8.8 %. Finally, ASW enhanced weight reduction (at 300 °C for 1 h) as the unit weight reduced by 1.75, 4.89, 3.30 and 1.86 % in C_89.5S₁₀A_0.5, C₈₉S₁₀A₁, C_88.5S₁₀A_1.5 and C₈₈S₁₀A₂, respectively, in comparison with C₁₀₀S₀A₀. Mayenite and muscovite could be formed as products when ASW is used as supplementary materials in silica fume blended mortar production.