Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study

For preserving concrete structures and hindering ingress of chemicals through cracks and fissures, repair is inevitable. Microbial calcite precipitation is an intrinsic approach for crack rectification and emulating way of sustainability for reducing anthropogenic greenhouse gases (GHGs) along with...

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Main Authors: Nafeesa Shaheen, Rao Arsalan Khushnood, Siraj Ud din
Format: Article
Language:English
Published: Wiley 2018-01-01
Series:Advances in Materials Science and Engineering
Online Access:http://dx.doi.org/10.1155/2018/7049121
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author Nafeesa Shaheen
Rao Arsalan Khushnood
Siraj Ud din
author_facet Nafeesa Shaheen
Rao Arsalan Khushnood
Siraj Ud din
author_sort Nafeesa Shaheen
collection DOAJ
description For preserving concrete structures and hindering ingress of chemicals through cracks and fissures, repair is inevitable. Microbial calcite precipitation is an intrinsic approach for crack rectification and emulating way of sustainability for reducing anthropogenic greenhouse gases (GHGs) along with conserving the natural resources. In this study, Bacillus subtilis strain is applied for intrinsic repair of concrete’s cracks because of its high pH endurance and capability of sporulation. For prolonged survival of microorganisms, immobilization technique was employed. B. subtilis was immobilized through limestone powder (LSP) before adding into cement matrix. Self-healing proficiency of B. subtilis was deliberated in terms of mechanical strength regain after cracking at 3, 7, 14, and 28 days. To examine the microstructure and characterization of healing precipitate, micrographical (field emission scanning electron microscopy), chemical (energy dispersive X-ray), and thermal (thermogravimetric analysis) analyses were performed after the healing period of 28 days. The results revealed evident signs of calcite precipitation in nano-/microcracks subsequent to microbial activity. Furthermore, immobilized LSP improved the compressive strength of the analyzed formulations.
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spelling doaj-art-0b383fb01da544e792fd6067a3ba558a2025-02-03T01:01:37ZengWileyAdvances in Materials Science and Engineering1687-84341687-84422018-01-01201810.1155/2018/70491217049121Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility StudyNafeesa Shaheen0Rao Arsalan Khushnood1Siraj Ud din2NUST Institute of Civil Engineering (NICE), School of Civil and Environmental Engineering (SCEE), National University of Sciences and Technology (NUST), Sector H-12, Islamabad 44000, PakistanDepartment of Structural, Geotechnical and Building Engineering (DISEG), Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, ItalyNUST Institute of Civil Engineering (NICE), School of Civil and Environmental Engineering (SCEE), National University of Sciences and Technology (NUST), Sector H-12, Islamabad 44000, PakistanFor preserving concrete structures and hindering ingress of chemicals through cracks and fissures, repair is inevitable. Microbial calcite precipitation is an intrinsic approach for crack rectification and emulating way of sustainability for reducing anthropogenic greenhouse gases (GHGs) along with conserving the natural resources. In this study, Bacillus subtilis strain is applied for intrinsic repair of concrete’s cracks because of its high pH endurance and capability of sporulation. For prolonged survival of microorganisms, immobilization technique was employed. B. subtilis was immobilized through limestone powder (LSP) before adding into cement matrix. Self-healing proficiency of B. subtilis was deliberated in terms of mechanical strength regain after cracking at 3, 7, 14, and 28 days. To examine the microstructure and characterization of healing precipitate, micrographical (field emission scanning electron microscopy), chemical (energy dispersive X-ray), and thermal (thermogravimetric analysis) analyses were performed after the healing period of 28 days. The results revealed evident signs of calcite precipitation in nano-/microcracks subsequent to microbial activity. Furthermore, immobilized LSP improved the compressive strength of the analyzed formulations.http://dx.doi.org/10.1155/2018/7049121
spellingShingle Nafeesa Shaheen
Rao Arsalan Khushnood
Siraj Ud din
Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study
Advances in Materials Science and Engineering
title Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study
title_full Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study
title_fullStr Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study
title_full_unstemmed Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study
title_short Bioimmobilized Limestone Powder for Autonomous Healing of Cementitious Systems: A Feasibility Study
title_sort bioimmobilized limestone powder for autonomous healing of cementitious systems a feasibility study
url http://dx.doi.org/10.1155/2018/7049121
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AT sirajuddin bioimmobilizedlimestonepowderforautonomoushealingofcementitioussystemsafeasibilitystudy