Estudo do comportamento mecânico de resíduo de mineração melhorado com cimento

Abstract

Major environmental disasters related to tailings dams have been occurring in Brazil over the last decade, with the collapse of the mining tailings dam called "Fundão" being cited. Different methods can be used to improve the performance and geotechnical properties of a mining tailings used in the construction of dams, and one of these methods is soil improvement. With this in mind, the aspects observed this research aim to characterize and determine parameters of strength and deformability of a gold mining tailings improved with cement through tests using a Simple Shear apparatus. Consolidated Undrained (CIU) tests were performed with different percentages of cement to quantify the influence of this variable on the parameters of strength and deformability of the material studied. Besides verifying the applicability of the porosity/volume content ratio of cement (η/Civ) in predicting the mechanical behavior of mixtures when facing monotonic and cyclic loads. It can be concluded that the increase in the content of cementing agent, and consequently a reduction of the parameter η/Civ, causes an increase in the cohesive intercept, while the friction angle of the material is not altered the friction angle of 34º was found independent of the cement amount. Under cyclic loading conditions of controlled deformation, the higher the level of deformation, the greater the shear modulus deformation. The liquefaction phenomenon did not occur for any of the studied dosages.