Mechanical properties of mortars with replacement of natural sand by steel slag BSSF (baosteel's slag short flow)

摘要

The waste production has become a relevant issue for the steel industry due to the large amount of waste generated. This waste amount requires appropriated planning in the destination. Additionally, the shortage of good quality inputs near of the consumer centers have increased the interest in products that cause less environmental impact with lower costs. This way, the present work presents has main aim the assessment of the mechanical properties of mortars with replacement of natural sand by steel slag Baosteel's Slag Short Flow (BSSF). The experimental work comprised the characterization of the mortar properties in the fresh state in the proportions of 1: 3, 1: 5, 1: 7 (cement; aggregate), 1: 1: 4, 1: 1: 6 and 1:1:8 (cement: lime: aggregate) . The replacement of natural sand by slag followed the rations of 0, 20, 40 and 60 % by volume. The results showed that mortars with higher slag contents required a higher quantity of water to obtain the fixed spread of 260 +/- 5mm. The replacement of sand by slag causes a significant increase in the density in the hardened state and in the dynamic modulus of elasticity for both hydraulic and composite mortars. For the ultrasonic propagation velocity (UPV), the substitution content does not influence hydraulic mortars significantly. However, a significant influence on mixed mortars was observed. Regarding the compressive strength and flexural tensile strength, despite 40% of replacement presented the highest values of tensile strength, the substitution content does not have a significant influence on these properties, according to the analysis of variance.