EXPERIMENTAL INVESTIGATION ON MECHANICAL, DURABILITY AND CRACK HEALING PROPERTIES OF BACTERIAL CONCRETE

Abstract

Concrete is one of the most commonly utilized building materials in construction projects around the globe. It is used in building foundations, columns, beams, slabs, shear walls, and other load bearing elements. Concrete structures have cracks that are a cause of concern for governments, project owners and final users. However, bacterial concrete is considered to be one of the best solutions to avoid the repair aspects of concrete due to its self-healing ability. Yet, few studies have been conducted on the effect of E. Coli bacteria on concrete. There is also a dearth of studies that experimentally examine the viability of E. Coli bacteria as a crack healing measure. Accordingly, the aim of this study was to experimentally investigate the viability of using E. Coli bacteria as a crack healing measure in concrete. In this respect, the impact of E. Coli bacteria in different percentages of E. coli bacteria was investigated by applying experimental techniques such as the slump and density tests on fresh concrete, compressive test, sorptivity test, water absorption test, temperature test, and crack healing test on hardened properties of concrete. The findings of the study revealed that E. Coli bacteria considerably minimizes concrete's drawbacks by precipitating calcium carbonate which heals cracks. Besides, it was found that in comparison to conventional concrete, concrete containing E. Coli bacteria has a higher potential for self healing, greater compressive strength, greater temperature resistance, and lower water absorption. In particular, concrete containing 3 percent E. Coli bacteria improves compressive strength better than concrete containing 5 percent and 1 percent E. Coli bacteria. The concrete with 5 percent of E. Coli bacteria heals the crack in a shorter period of time but it results in lower compressive strength than the concrete with 3 percent of E. Coli bacteria. Thus, the concrete containing present E. Coli bacteria is less preferable to the concrete with 3 percent E. Coli bacteria in terms of improving compressive strength.