An Experimental Investigation on Bacteria incorporated Concrete

Abstract

Concrete is the extensively used manmade construction material in civil engineering newlineconstructions. It can be casted in any desirable shape yet plain concrete anyway has lower tensile newlinestrength and ductility along with lesser resistance to cracking. Concrete technology has advanced newlinein terms of strength of the concrete which alone cannot suffice the severe environmental newlineconditions since concrete is exposed to its entire life-span. Hence it becomes imperative that both newlinestrength and durability must be considered at the early phase of design and to produce a durable newlinestructure. A technique of self healing can be used to build strong durable structures of concrete newlinewhich is advantageous and economical. The process of continuous production of calcite newlineprecipitation in concrete by addition of spore forming bacteria is called Bacterial concrete. This newlinemethod is also known as Microbiologically Induced Calcite Precipitation (MICP). The essential newlinestandard for this procedure is that the microbial urease hydrolyzes urea to produce ammonia and newlinecarbon dioxide and the ammonia released leads to increase in pH and accumulation of non- soluble calcium carbonate. It is observed that the concrete strength and crack repairs can be newlineimproved by culturing of bacteria. The main aim of this research is to study the effect of different bacteria s on the strength newlineand durability properties of bacterial concrete. The concrete mixes are prepared using different newlinecell concentrations (100 newline, 103 newline, 105 newline, 107 cells/ml of mixing water). Strength and durability tests newlinewere conducted at the age of 28 days. The study is done on M 25 grade of concrete. The effect of newlineaddition of different bacteria s in concrete to improve the strength and durability properties is newlinefound out in this research work. In addition, the effect of bacteria in concrete with cement newlinereplacement materials such as fly ash, GGBFS and silica fume by 20% of weight is found out newlinesuch that the bacterial concrete combines the merits of bacterial calcite precipitation and the use newlineof sustainable materi