Research on Mechanical Properties and Hydration Characteristics of Pyrite Tailings Foam Concrete

In order to explore the influence of foaming agent, water-binder ratio, tailings specific surface area and fiber on pyrite tailings foamed concrete the compressive strength tests of concrete were carried out and the optimal types and proportions of the above ingredients were obtained for the subsequent exploration of the influence of the amount of pyrite tailings on the strength of foam concrete. The test results show that with the increase in the amount of pyrite tailings the compressive strength of the foam concrete gradually decrease, and when the amount is 20%-30% the compressive strength of foam concrete decreases most. In the DSC-TG tests it is found that the increase in the amount of pyrite tailings will lead to the reduction of hydration products, thereby reducing the compressive strength of the foamed concrete. Through IR tests found that an increase in the amount of doping will lead to a decrease in OH-, Si-O bonds and Al-O bonds. This represents the reduction of hydration products C-S-H gel and wollastonite Thereby its compressive strength was reduced; the heat of hydration tests not only found that the increase in the amount of doping will decline its mechanical properties. It is also found that the strength provided by pyrite tailings to foamed concrete is mainly after the protection age of 50 h. Therefore, adding appropriate amount of pyrite tailings to foamed concrete can improve its compressive strength.