Influence of the Parameters of an Alumosilicate Additive Based on Mountain Sand on the Properties of Sulfate-Resistant Portland Cement

Abstract

The paper substantiates the effectiveness and prospects of research in the direction of developing an active mineral additive based on mountain sand of Yakutia for general construction cements in order to increase its sulfate resistance. This will expand the range of application of Portland cements operating in conditions of sulfate aggression. The Republic of Sakha (Yakutia) has many deposits of natural sands of aluminosilicate composition or the so-called "mountain sands". One of the large and developed quarries of mountain sands in Yakutia is the Kildyamskoye deposit. Today it is used for foundations and underlying road surfaces. The paper shows the possibility of obtaining an active mineral additive based on this sand. The influence of the dosage and dispersion level of the additive on the strength characteristics of cements and on the coefficient of sulfate resistance is studied in the range of 5±2 % while maintaining brand strength. The introduction of an additive of more than 15 % reduces the strength of cement by an average of 20%, the grade strength is no longer observed, while hydration processes slow down and over time in a sulfate environment, the strength of the samples first increases and then falls again. As a result of the work, an active mineral additive based on the sand of the Kildyamskoe deposit in cement is proposed. This gives a stable sulfate resistance coefficient equal to 0.95 while maintaining brand strength and hydration processes.