Analysis of Physical changes due to bacterial remediation in LECA LWA Concrete

Abstract

The use of lightweight concrete aggregate in structures can offer advantages such as a reduction in dead load along with a reduction in plate and beam dimensions. Considering its use, artificial LWA’s significantly lower costs are also crucial. Whilst lightweight concrete aggregate is more water absorbed and more porous, design strategies can be used and applied with difficulty.The treatment of LWA with chemicals, together with several other unintended side effects, has proven effective but not environmentally friendly. This led to a study into the fields of biology for a proper solution to the problems.The use of microbiologically induced calcite precipitation was a forerunner in this investigation. This paper describes the physical effects of Bacillus Sphaericus on Lightweight Aggregate Concrete when exposed to it in a Calcitrate and LML extract medium, as well as an analysis of the effects of surface treatment via the bacteria on the LWA. For this study, the LWA were submerged in the Calcitrate and LML Extract solution for half an hour, then drained and kept in an oven at 39°C for 4 days, and after repeating twice, they were used in the mix according to the mix design, and the effects were observed.The results showed a reduction of 5% in water absorption, 15% increase in comp. strength and Higher Workability than standard samples.