Evaluation of the durability of mortars with partial replacement of cement by nickel slag in marine environments

Abstract

The nickel slag evaluated in this work, is an industrial waste of the Lomas de Níquel mining company, which is produced during the exploitation and processing of the same. It is a contaminant for both the environment and the people living in the vicinity of the mine. The manufacture of reinforced concrete with partial replacement of cement by slag, would decrease both the industrial waste of the environment, and the content of cement in the mixtures, reducing costs, provided that mixtures with durable physical, mechanical and electrochemical properties are obtained. The objective of this study is to elaborate mortars, replacing part of the cement of its mixture design, by different contents of nickel slag (20, 30 and 40 %p/p), in order to determine its durable properties; and with these results, to be able to make reinforced concrete to be used in the construction and/or repair of structures exposed to aggressive environments with chlorides. For the study, mortars with different water/cement ratios (0.4 and 0.6) were made and evaluated by means of different tests: physical (capillary absorption and effective porosity), mechanical (resistance to compression) and electrochemical (measurements of potential and corrosion speed in time). The results obtained so far, which are part of a research project that is currently underway, indicate that the mortar mixtures with a c/r ratio of 0.4 and the replacement of cement by nickel slag of 20 %p/p, produce favorable durable properties.