Performance and Micro Structural Analysis of Portland Slag Cement Mortar Induced with Pozzolanic Additives

Abstract

Portland cement is a kind of cement used where the high strength and durability is needed. Also, this type of cement is essentially used to control the CO2 emission during the manufacturing process of the concrete. This cement is made up of slag with the activator such as alkalis in the form of sodium hydroxide or sodium silicate. However, this addition is increasing the overall cost of the production of concrete. In this research, a new attempt has been made to use the natural activators of Rice Husk Ash (RHA) and Natural Steatite Powder (NSP). This research aims to determine the effects of RHA and NSP with Portland slag cement by partial replacement with 5%, 10%, 15% and 20% of RHA and NSP. The influence of the RHA and NSP on the mechanical properties of the mortar was evaluated by measuring the compressive strength and the split tensile strength. The durability properties of the specimens were analyzed by water absorption, sorpitivity and acid attack tests. The analysis of the microstructure of the specimens was done by scanning electron microscope (SEM) and Fourier Transform Infrared Spectra analysis (FTIR). It was observed that the maximum compressive strength and split tensile strength was in 5% RHA and NSP blended mortar. The durability results showed that the 10% RHA and 10% NSP had lesser water absorption and sorpitivity values. From the results of micro structural analysis it was observed that replacing cement with 5% RHA and 5% NSP results in improvement of microstructure of cement mortar.