Advantages of adding copper tailings sand to concrete

March.21,2023

In this paper, copper tailings sand and natural sand were used as fine aggregates to prepare C50 concrete, and the effects of copper tailings sand content on concrete mechanical properties, chloride ion permeability resistance, drying shrinkage performance and frost resistance were studied, and the bulk resources of copper tailings were evaluated. feasibility of utilization.

(1) When the content of copper tailings sand is 10%~30%, the compressive and flexural strength of copper tailings sand concrete is higher than that of natural river sand concrete. When the copper tailings content is 30%, the 28-day compressive strength and flexural strength of the copper tailings concrete are 8.9% and 15.4% higher than those of the natural river sand concrete; when the copper tailings content is 40%, the copper tailings concrete The compressive and flexural strength of concrete is comparable to or slightly lower than that of natural river sand concrete.

(2) The drying shrinkage rate of copper tailings sand concrete is higher than that of natural river sand concrete, and increases with the increase of copper tailings sand content. When the copper tailings sand content is 40%, the 90-day drying shrinkage rate is the largest. Compared with natural river sand concrete, it is 11.6% larger.

(3) The electric flux of copper tailings concrete is smaller than that of natural river sand concrete, and when the content of copper tailings is 30%, the electric flux of concrete is the smallest, which is 45.6% lower than that of natural river sand concrete. The incorporation of copper tailings improves the chloride ion penetration resistance of concrete.

(4) After 200 freeze-thaw cycles, both copper tailings concrete and natural river sand concrete lost no more than 1% of their mass, and the frost resistance of concrete mixed with an appropriate amount of copper tailings sand was better than that of natural river sand concrete.