Self-healing of cement mortar with partial replacement of cement with silica fume

Abstract

Many attempts are being made to use alternative building materials for sustainable construction practices. Huge research work being conducted to identify materials which can be partially replaced by cement. Here we tried to use silica fume & pseudomonas fluorescens as a partial replacement of cement which is having capability of self-healing in cement mortar. Efforts has been made to develop resources with minimal use of fossil fuel based on non-renewable resources which has negative impact on environment. Hence reducing ecological disturbances making biologically efficient. Many industries have been exploring way for variety of bacterial properties to introduce in construction line. Cracks occurring in cement mortar will result into the decrease in its durability property. Hence there is a great demand for effective yet eco-friendly alternative technique for reducing cracks in cement mortar. Reduction of cost can be achieved by bacterial self-healing cement mortar in terms of damage spotting and maintenance of cement mortar. This project presents effect of the bacteria (pseudomonas fluorescens) on strength and durability properties of sustainable cement mortar. Optimized bacterial concentrations of 107 cells/ml and 108 cells/ml were used for designing of mortar mix proportions. Silica fume is added at 5%, 10%, 15%, 20%, and 25% by weight of cement for replacing of cement in the 1:3 cement mortar mix. Compressive strength, split tensile strength and flexural strength tests were performed on mortar cubes at the age of 7 & 28 days. The obtained results are evident that, addition of pseudomonas fluorescens bacteria in mortar mix will enhance the mechanical and durability properties in cement mortar.