Study of Strength Variation of Concrete Using Ureolytic Bacteria

Satinder Kaur Khattra, Manisha Parmar, Urmila Gupta Phutela

This paper presents the results of a study carried out to investigate the ability of ureolytic bacteria to enhance the compressive strength of concrete. The urease producing aerobic alkalophilic bacteria Bacillus subtlis strain MU12 was used in the present study. Ureolytic bacteria used in the present studies were isolated from various sources like cowshed, poultry farm, milk, soil and pigeon dung. All the isolates were screened for ureolytic activity on the basis of urease test. These isolated cultures were purified on phenol red agar plates.  Four different cell concentration (10⁴, 10⁵,10⁶,10⁷ cells/ml) of bacteria were used in making the concrete mixes. Tests were performed for compressive strength of concrete cubes at 7 days, 14 days and 28 days. Inclusion of MU12 @ 10⁷ cells/ ml in cement concrete enhanced the compressive strength in 7^th and 14^th days concrete samples.