Use of spores forming bacteria to produce material that have ability to repair cracked concrete effected by environmental conditions

Abstract

The aim of project to develop and test specific types of self –healing concrete, these achieved by isolated specific local types of bacteria, and test its ability to repair cracks which found in concrete according to bacterial ability to enhance metabolism for precipitate calcium carbonate and repair the concrete cracks. We obtained four local alkalophilc spore forming isolated bacteria. Self healing ability was tested for isolates , Results show increase in compressive strength values for treated cement sample with AC1 isolate in comparison with other isolates and control .The treated sample with AC1 isolate was increase 9.2% if compared with reference cement mortar ,also we examined the treated cement samples with ESEM (environmental scanning electron microscope).Results indicated that the AC1 isolate showed high variation in comparison with control and other isolates, that the pores and internal space became very few ,also the surfaces were smooth .The isolates were identified and diagnosed as Bacillus subtilis .