Ramdas, VesharaLalloo, RajeshMandree, PrishaMgangira, Martin BMukaratirwa, SamsonRamchuran, Santosh O2022-10-032022-10-032022-02Ramdas, V., Lalloo, R., Mandree, P., Mgangira, M.B., Mukaratirwa, S. & Ramchuran, S.O. 2022. Performance evaluation of bio-based fractions derived from Bacillus spp. for potential in situ soil stabilisation. <i>Applied Sciences, 12(4).</i> http://hdl.handle.net/10204/124902076-3417https://doi.org/10.3390/app12041774http://hdl.handle.net/10204/12490Current and future research focuses on the use of renewable technologies and materials to stabilise weak soils, of varying degrees, for road construction applications. Soil stabilisation is a method of strengthening a natural soil to meet this purpose. Our interest is in the use of bio-based components, derived from microbial growth processes, that contribute to the needed desirable strength characteristics for in situ soil stabilisation. This investigation focuses on novel Bacillus-based stabilisers obtained from the vegetative and spore growth stage. In this study, eighteen bio-based components were derived from a Bacillus licheniformisfermentation and extracted into various aqueous and non-aqueous fractions for strength property assessment. The strength properties of the treated soils (i.e., dolerite and weathered granite soil) were assessed via previously developed lab-scale equipment to rapidly pre-select the best performing fractions, (i.e., compression stress, erosion, abrasion, and water absorption tests). The effect of one superior performing prototype (a) was validated at large-scale, using standard erosion and abrasion tests (i.e., whole broth at 1.8% stabiliser concentrations), and showed resistance to abrasion (3.37 ± 0.03%) (p value = 0.0001) and resistance to erosion (33.20 ± 0.15%) (p value = 0.001). The elemental composition and microstructure of the bio-stabilised soil was determined using energy dispersive X-ray spectroscopy and scanning electron microscopy, respectively. This evaluation formed part of the selection of the best performing Bacillus derived fractions and achieved a proof of concept for the next phase of product prototype development. This study demonstrated a novel bio-mediated approach to the overall criteria for evaluation and selection of candidate product prototype/s, for stabilisation of two varying soils, and for potential application in road construction works.FulltextenBacillus speciesBio-stabilisersBio-polymersMicrobial componentsSoil stabilisationUnpaved roadsArticleRamdas, V., Lalloo, R., Mandree, P., Mgangira, M. B., Mukaratirwa, S., & Ramchuran, S. O. (2022). Performance evaluation of bio-based fractions derived from Bacillus spp. for potential in situ soil stabilisation. <i>Applied Sciences, 12(4)</i>, http://hdl.handle.net/10204/12490Ramdas, Veshara, Rajesh Lalloo, Prisha Mandree, Martin B Mgangira, Samson Mukaratirwa, and Santosh O Ramchuran "Performance evaluation of bio-based fractions derived from Bacillus spp. for potential in situ soil stabilisation." <i>Applied Sciences, 12(4)</i> (2022) http://hdl.handle.net/10204/12490Ramdas V, Lalloo R, Mandree P, Mgangira MB, Mukaratirwa S, Ramchuran SO. Performance evaluation of bio-based fractions derived from Bacillus spp. for potential in situ soil stabilisation. Applied Sciences, 12(4). 2022; http://hdl.handle.net/10204/12490.TY - Article AU - Ramdas, Veshara AU - Lalloo, Rajesh AU - Mandree, Prisha AU - Mgangira, Martin B AU - Mukaratirwa, Samson AU - Ramchuran, Santosh O AB - Current and future research focuses on the use of renewable technologies and materials to stabilise weak soils, of varying degrees, for road construction applications. Soil stabilisation is a method of strengthening a natural soil to meet this purpose. Our interest is in the use of bio-based components, derived from microbial growth processes, that contribute to the needed desirable strength characteristics for in situ soil stabilisation. This investigation focuses on novel Bacillus-based stabilisers obtained from the vegetative and spore growth stage. In this study, eighteen bio-based components were derived from a Bacillus licheniformisfermentation and extracted into various aqueous and non-aqueous fractions for strength property assessment. The strength properties of the treated soils (i.e., dolerite and weathered granite soil) were assessed via previously developed lab-scale equipment to rapidly pre-select the best performing fractions, (i.e., compression stress, erosion, abrasion, and water absorption tests). The effect of one superior performing prototype (a) was validated at large-scale, using standard erosion and abrasion tests (i.e., whole broth at 1.8% stabiliser concentrations), and showed resistance to abrasion (3.37 ± 0.03%) (p value = 0.0001) and resistance to erosion (33.20 ± 0.15%) (p value = 0.001). The elemental composition and microstructure of the bio-stabilised soil was determined using energy dispersive X-ray spectroscopy and scanning electron microscopy, respectively. This evaluation formed part of the selection of the best performing Bacillus derived fractions and achieved a proof of concept for the next phase of product prototype development. This study demonstrated a novel bio-mediated approach to the overall criteria for evaluation and selection of candidate product prototype/s, for stabilisation of two varying soils, and for potential application in road construction works. DA - 2022-02 DB - ResearchSpace DP - CSIR J1 - Applied Sciences, 12(4) KW - Bacillus species KW - Bio-stabilisers KW - Bio-polymers KW - Microbial components KW - Soil stabilisation KW - Unpaved roads LK - https://researchspace.csir.co.za PY - 2022 SM - 2076-3417 T1 - Performance evaluation of bio-based fractions derived from Bacillus spp. for potential in situ soil stabilisation TI - Performance evaluation of bio-based fractions derived from Bacillus spp. for potential in situ soil stabilisation UR - http://hdl.handle.net/10204/12490 ER -25939