Biomineralization in metakaolin modified cement mortar to improve its strength with lowered cement content

Li, Mengmeng; Zhu, Xuejiao; Mukherjee, Abhijit; Huang, Minsheng; Achal, Varenyam

doi:10.1016/j.jhazmat.2017.01.035

Cited by 100 publications

(28 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As a result of growing knowledge on carbonate biomineralization, applications in concrete repair and formulation of self-healing cement have been derived (Achal et al, 2009;Li et al, 2017;Seifan et al, 2016;Singh et al, 2015). Additionally, carbonate formation for remediation purposes, including wastewater treatment (Gonzalez-Martinez et al, 2017), has gained interest (Kumari et al, 2016;.…”

Section: Introductionmentioning

confidence: 99%

Calcium carbonates: induced biomineralization with controlled macromorphology

et al. 2017

View full text Add to dashboard Cite

Abstract. Biomineralization of (magnesium) calcite and vaterite by bacterial isolates has been known for quite some time. However, the extracellular precipitation has hardly ever been linked to different morphologies of the minerals that are observed. Here, isolates from limestone-associated groundwater, rock and soil were shown to form calcite, magnesium calcite or vaterite. More than 92 % of isolates were indeed able to form carbonates, while abiotic controls failed to form minerals. The crystal morphologies varied, including rhombohedra, prisms and pyramid-like macromorphologies. Different conditions like varying temperature, pH or media components, but also cocultivation to test for collaborative effects of sympatric bacteria, were used to differentiate between mechanisms of calcium carbonate formation. Single crystallites were cemented with bacterial cells; these may have served as nucleation sites by providing a basic pH at short distance from the cells. A calculation of potential calcite formation of up to 2 g L −1 of solution made it possible to link the microbial activity to geological processes.

show abstract

Section: Introductionmentioning

confidence: 99%

Calcium carbonates: induced biomineralization with controlled macromorphology

et al. 2017

View full text Add to dashboard Cite

show abstract

“…e calcite precipitated by microbes within the cementitious matrix actually plugs the pores, and hence, contributes in improvement of compressive strength. e reaction kinetics in the presence of microbes also endorses the formation of additional CSH gel as a result of CO 2 consumption as revealed by Li et al, which further adds in compressive strength [39]. e involved chemical reaction is as follows:…”

Section: Compressive Strength Analysismentioning

confidence: 88%

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

Shaheen

Khushnood

Din

2018

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

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 subtilisstrain 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. subtiliswas immobilized through limestone powder (LSP) before adding into cement matrix. Self-healing proficiency ofB. subtiliswas 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.

show abstract

“…e two bands at ∼460 cm − 1 and ∼523 cm − 1 corresponded to the bending vibration of the Si-O bond. e difference in relative intensities of the absorption peak at 871 cm − 1 indicated that the content of C-S-H gel in coral mortar was higher than that in standard mortar [32]. is was because Ca 2+ and Mg 2+ ions from coral sand continuously participated in hydration reaction, generating more hydration products [33,34].…”

Section: Xrd Analysismentioning

confidence: 99%

Mechanical Properties and Microscopic Mechanism of Coral Sand‐Cement Mortar

Wang

Mei

et al. 2020

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

e workability and mechanical performance of coral sand-cement mortar (coral mortar, for short) and the modification effects of mineral admixtures on the coral mortar were studied in this paper. e results showed that the strength of coral mortar was lower than that of standard mortar, but the strength of coral mortar was improved by compositing with the mineral admixture, which can be attributed to the improvement of the microstructure and interface transition area. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were used to explore the microscopic mechanism involved in the mechanical properties, volume stability, and hydration of mortar. e analyses revealed that the internal curing effect of coral sand improved the mechanical properties of mortar and its ability to resist shrinkage. e uneven surface of coral sand formed a meshing state of close combination with the hardened cement mortar, which helped to improve the volume stability of mortar. e Ca 2+ and Mg 2+ ions from coral sand participated in the hydration reaction of cement, which contributed to generating more hydration products. Moreover, the microaggregate filling and pozzolanic effects of fly ash and slag improved the mechanical properties of coral mortar and resistance to chloride ion diffusion.

show abstract

Biomineralization in metakaolin modified cement mortar to improve its strength with lowered cement content

Cited by 100 publications

References 28 publications

Calcium carbonates: induced biomineralization with controlled macromorphology

Calcium carbonates: induced biomineralization with controlled macromorphology

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

Mechanical Properties and Microscopic Mechanism of Coral Sand‐Cement Mortar

Contact Info

Product

Resources

About