Self-Healing Concrete Using Bacteria Calcification from Karst Cave Environment

Abstract

Karst regions in Indonesia have the uniqueness of the landscape and biodiversity. The karst is formed by the dissolution of rocks and the precipitation of mineral. In the cave, there are ornaments of stalactite and stalagmite which are formed by the process of mineral precipitation. We have isolated, screened, and identified the soil bacterium from the cave environment (Lysinibacillus macroides). These bacteria are able to precipitate calcium carbonate and can be developed as a self-healing agent concrete. We investigated the proportions and the properties of mixtures concrete containing lightweight aggregate and volcanic ash impregnated with bacteria. A comparison study was made by concrete cylinders subjected to compressive strength tests with and without the bacteria. It found that the strength of concrete with bacteria decreased by less than 10.56% for 28 days of cured specimens. This study showed that the effects of bacteria on the strength of concrete are not considerable. However, these bacteria are effective to repair in the microcrack less than 0.3 mm

Microbially induced calcium carbonate precipitation in broiler litter and its effect on soil pH

“…This specific isolate was identified as Lysinibacillus macroides (MT197307), and members of this genus have been previously identified in poultry manure (Sudha et al., 2022). This genus of bacteria includes ureolytic and non‐ureolytic strains that are capable of precipitating CaCO 3 in the presence of Ca 2+ (Banerjee & Joshi, 2014; Lee & Park, 2019; Nugroho et al., 2019). After incubating the two broiler litter treatments with the ureolytic isolate, the pH of the litter treated with gypsum (8.4 ± 0.026) was significantly less than that of the litter without gypsum (8.6 ± 0.006) ( p < 0.001).…”

Bioprecipitation of calcium carbonate by Bacillus subtilis and its potential to self-healing in cement-based materials

“…Investigations using the above-mentioned approaches have been conducted with a view to developing a special type of concrete referred to as 'bacterial concrete,' in which bacteria are induced to mortars and concretes to heal micro-cracks as they appear. The development of self-healing materials by microbialinduced precipitation has been examined in several studies using bacteria of the Bacillus genus, showing an increase in the durability and mechanical properties of the concrete and a decrease in chloride permeation (Dessai, Panandikar, Ramarajan, & Pillai, 2019;Hussein, Abedali, & Ahmead, 2019;Nugroho et al, 2019;Tayebani & Mostofinejad, 2019b). Regardless, as mentioned previously, several studies have used ureolytic bacteria and CaCl 2 ; however, degradation of urea produces ammonia as a bad odor and CaCl 2 can be harmful to reinforced concrete structures due to the addition of Cl -1 , which is responsible for corrosion.…”