Analysis of cementitious matrices self-healing with bacillus bacteria

Abstract

Bacterial solutions have been studied to promote self-healing of cementitious matrices, however, the concentration of this solutions varied between studies. Consequently, the objective of this study was to evaluate the self-healing potential of different concentrations of Bacillus subtilis AP91 encapsulated in expanded perlite (EP). Visual examination and capillary absorption of water was measured over time. Test samples were also subjected to strength resistance tests. The physiochemical properties of EP and his distribution on the matrix was evaluated. There was no observable trend in the effect of solution concentration on the width of crack healed. However, concentration affected the quantity and length of the fissures healed. Capillary absorption decreased as fissures were healed while no significant changes were measured in strength resistance regardless of the concentration. Results indicated that EP provided suitable encapsulation to the bacterial solution and there is an adequate distribution of the capsules in the cementitious matrix.

Evaluation of concrete self-healing by encapsulated sodium metasilicate in perlite and expanded clay

“…Consequently, in this study, if a crack appeared along a region of smaller particles, there was a chance that the substitute aggregate did not fracture and sodium metasilicate was not exposed to humidity. Those results of cicatrization occurrence being affected by the crack area, the surface characteristics, and the healing product availability were also pointed out by Pacheco et al [34] and Muller et al [47]. Overall, EP substitution achieved between 57.58% and 100% healing of the crack while EC substitution achieved between 12.63% and 90% healing.…”

Effect E. coli Bacteria Concentration as Self Healing on Compressive Strength and Hydrophobic Properties on Micro Cracks of Concrete

“…To make concrete hydrophobic, you can include bacteria in the manufacturing process. Some bacteria are known to be able to carry out self-healing because their metabolism can produce lime which can then fill the q pores in concrete (Bandlamudi et al, 2022;Muller et al, 2021;Orozco et al, 2022). Self-healing in concrete is the ability of concrete to repair itself when it experiences cracks.…”

Avaliação da capacidade de autocicatrização de argamassas especiais contendo aditivo mineral cristalizante e agentes biológicos

“…Este fenômeno promovido pelas reações tardias da própria matriz é conhecido como autocicatrização autógena. Além disso, no âmbito da tecnologia dos materiais da construção, o uso de aditivos minerais cristalizantes (ZIEGLER et al, 2020) e agentes biológicos, como bactérias precipitadoras de CaCO3 (MULLER et al, 2022;SCHWANTES-CEZARIO et al, 2022), também pode contribuir para minimizar a fissuração e melhorar a durabilidade. O fechamento de fissuras promovido por agentes potenciais de colmatação adicionados na matriz configura o fenômeno de autocicatrização autônoma.…”