Study on the Use of Tailings Sludge from the Ta Phoi Copper Concentration Plant as a Replacement for Natural Sand in the Production of Cement-Free Green Concrete

Abstract

This paper presents the experimental results on the use of waste mud from the Ta Phoi Copper Processing Plant as a partial replacement for natural fine aggregates in the production of green concrete without cement. The plant generates approximately 60,000 m³ of waste mud and tailings per month, posing significant challenges to storage capacity and environmental safety. The study follows current Vietnamese standards to evaluate the workability and compressive strength of green concrete mixtures containing 0÷30% waste mud. The resulting mixtures exhibited good workability with slump values ranging from 14.5 to 20.0 cm, stable bulk densities, and 28-day compressive strengths exceeding 40 MPa. The optimal mixture containing 10% waste mud achieved the highest compressive strength of 55.5 MPa. These findings demonstrate the potential of waste mud to function as an artificial fine aggregate, offering a sustainable solution to reduce natural sand consumption, manage industrial waste, and promote eco-friendly construction materials..