Biomodified building materials on the base of mineral binders

Abstract

In order to increase the service life of structures, there should be taken various measures aimed at damaged elements restoration followed by their due maintenance. Enhancing material’s properties by the ability of self-healing is done with the help of the additive and is seen as the effective method of preservation of the materials’ properties. The analysis of the previous studies has shown that biological and biochemical processes are given preference to facilitate self-healing process. The purpose of the present study was a development of the method allowing for the increase in durability of buildings structures by activating and providing self-healing processes of building materials. The application of the developed bioadditive allows retaining reliability of construction products at the very initial stages of microflaws’ appearance by filling them up with the essential products of bacteria with urease activity. The bacteria are introduced into the body of the material at the manufacturing stage. This method of imparting a self-healing effect to the materials has many points in its favor such as sustainability, cost effective performance, and reduced labor costs for repair and restoration work. The method could be used in the structures of any complexity and for reconditioning of heritage sites. The selected microorganisms act upon the mix as surfactants, that is, they lower the water-cement ratio of sand-cement mortars by augmenting the concentration of bio-surfactants. This feature of cells enhances the efficiency of the developed additive. Application of these microorganisms as a component of a biologically active additive can significantly increase production performance and the efficiency of building structures’ operation due to higher efficiency of microorganisms responsible for initiating self-healing processes in building materials. According to the research results, zeolite could be regarded as the most suitable porous material acting as a carrier of cell immobilization.