Research On The Iron Ore Tailings Powder Admixture And Its Concrete Performance

In the process of iron ore mining, producing a large amount of tailings solid waste, the accumulation not only takes up land, results in environmental pollution, causes ecological damage, but also poses a security threat. At present, the utilization of iron ore tailings is still very low, there is an urgent need to seek new methods to deal with and apply the iron ore tailings. On the other hand, there is a great consumption of concrete in our country, the amount of concrete is more than 7 billion cubic meters in 2014, the annual demand for mineral admixture should be more than 800 million tons. Due to the uneven distribution of fly ash, slag and other industrial waste, the reducing of coal-fired power plants and the output of fly ash and other waste, many general admixture are in short apply in many parts of the South, There is a need to develop new admixture as a supplement objectively. Iron ore tailing particles belong to the category of special fine sand mostly, only a small amount can be used as a mechanism sand. Iron tailings pulverized into powder as mineral admixtures used in concrete, which not only can alleviate the problem of shortage of mineral admixture, but also consumes a large amount of tailings waste. Besides, it can bring considerable economic and environmental benefits.This paper mainly studies the applicability of fine iron tailings powder as mineral admixture in concrete, Clarifies the technical requirement of iron ore tailings powder and its influence on concrete performance, hope to form the main technical points of the application of iron tailings powder concrete, and promote the wide application of iron ore tailing powder in concrete engineering.Topics for iron tailings powder suitable technical indicators, suitable dosage in the concrete, the workability, strength and durability and other aspect has carried on the system research, and by scanning electron microscopy(SEM) test, microstructure and micro powder floating are discussed. The results show that: the iron tailings powder fineness control in 500m2/kg, methylene blue value was lower than 1, iron ore tailings powder and slag powder mixed with the ratio of 5:5 to 6:4 in the range, and compound mineral admixtures in cementations material content is not more than 40%, iron tailings powder mixed with concrete, has good workability, strength meet the requirements of concrete grade, and the influence on the durability of fly ash. Iron ore tailings powder particles are uniformly distributed in the slurry, the anti floating, ability is obviously better than that of fly ash, excellent wear resistance. The research proved that iron tailings powder as concrete admixture with technical feasibility.