Critical aspects in the handling of reactive silica in cementitious materials: Effectiveness of rice husk ash vs nano-silica in mortar dosage

Torres-Carrasco, M.; Reinosa, J.J.; Rubia, M.A. de la; Reyes, E.; Alonso-Peralta, Francisco; Fernández, J.F.

doi:10.1016/j.conbuildmat.2019.07.023

Cited by 40 publications

(14 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Even though the incorporation of nanosized materials such as C-S-H, silica nanoparticles, carbon nanotubes, titanium dioxide, and others has been widely studied in the literature of the last two decades (Spinazzè et al 2016;Bossa et al 2017;Diamond et al 2017;Miller et al 2017), still, there are strong concerns regarding the handling and safety of using nanosized admixtures during cement-based composites production, as well as during the demolition works (Lee et al 2010;Van Broekhuizen et al 2011;Jones et al 2016;Strokova et al 2018;Torres-Carrasco et al 2019). There are many factors affecting the potentially hazardous effects of nanomaterials arising from their size, shape, chemical composition, the tendency to agglomerate, solubility, surface area and charge (Nawrotek and Augustyniak 2015;Miller et al 2017;Augustyniak et al 2019).…”

Section: Introductionmentioning

confidence: 99%

The effects of calcium–silicate–hydrate (C–S–H) seeds on reference microorganisms

et al. 2020

View full text Add to dashboard Cite

Building materials are constantly improved with various additives and admixtures in order to achieve goals ranging from obtaining increased durability or antimicrobial activity up to reducing the carbon footprint left by the cement production. Since nanomaterials were proposed for cement products, many studies explored the possibilities for their incorporation. One of the novel trends in studying these materials is evaluating their impact on living organisms, with the focus not only on toxicology but also on the application potential. Therefore, in this study, we investigated the effects of three types of calciumsilicate-hydrate (C-S-H) seeds on reference microorganisms in the scope of their basic physiology and primary metabolism. Shape, size and elemental composition of C-S-H seeds were also evaluated. The tests on the reference microorganisms have shown that the reaction to these nanomaterials can be specific and depends on the strain as well as the type of used nanomaterial. Furthermore, the presence of C-S-H seeds in the growth environment led to metabolic stimulation that resulted in faster growth, higher biochemical activity, and increased biofilm formation. Based on our findings, we conclude that even though C-S-H seeds have antimicrobial potential, they can be potentially used to promote the growth of selected microbial strains. This phenomenon could be further investigated towards the formation of beneficial biofilms on building materials.

show abstract

Section: Introductionmentioning

confidence: 99%

The effects of calcium–silicate–hydrate (C–S–H) seeds on reference microorganisms

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The fineness moduli of the fine aggregates used in various experimental studies in mortar vary between 2.4 and 2.8, while the specific gravity values vary between 2.45 and 2.65 [ 29 , 73 , 84 , 85 ]. The binder/sand ratio is generally kept between 1:2 and 1:4 [ 36 , 78 , 86 , 87 ]. ASTM C-778 is used to identify the grading curve of a fine aggregate [ 84 ].…”

Section: Methodsmentioning

confidence: 99%

“…A denser and stronger matrix is formed by the nano-silica after reaction with calcium hydroxide to form the C–S–H gel [ 19 , 128 ]. The reduction in strength beyond the optimum dosage is due to uneven dispersion and agglomeration of nano-silica in the matrix, leading to formation of weak zones within the mortar matrix [ 78 ].…”

Section: Properties and Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Comparative Overview of the Performance of Cementitious and Non-Cementitious Nanomaterials in Mortar at Normal and Elevated Temperatures

et al. 2021

View full text Add to dashboard Cite

Nanotechnology has emerged as a field with promising applications in building materials. Nanotechnology-based mortars are examples of such building materials that have widespread applications in the construction industry. The main nanomaterials used in mortars include nano-silica, nano-magnesium oxide, nano-alumina, nano-titanium oxide, nano-zinc oxide, nano-clay, and nano-carbon. This review paper presents a summary of the properties and effects of these nanomaterials on cement mortar in terms of its fresh-state and hard-state properties. The fresh-state properties include the setting time, consistency, and workability, while the hard-state properties include mechanical properties such as compressive, flexural, tensile strengths, as well as the elasticity modulus, in addition to durability properties such as water absorption, shrinkage strain, strength loss due to freeze–thaw cycles, and chloride penetration, among others. Different nanomaterials cause different physical and chemical alterations within the microstructures of cement mortar. Therefore, the microstructural characterization and densification of mortar are discussed in detail at varying temperatures. In general, the involvement of nanomaterials in cement mortar influences the fresh-state properties, enhances the mechanical properties, and impacts the durability properties, while reducing the porosity present in the mortar matrix. Cementitious nanomaterials can create a pathway for the easy injection of binding materials into the internal microstructures of a hydration gel to impact the hydration process at different rates, whereas their non-cementitious counterparts can act as fillers. Furthermore, the research gaps and future outlook regarding the application of nanomaterials in mortar are discussed.

show abstract

“…In recent years, there is a growing concern about the safety of using NPs in cementitious composites. Thus, the amount of the research works increased substantially (Bräu et al 2012;Spinazzè et al 2016;Bossa et al 2017Bossa et al , 2019Diamond et al 2017;Miller et al 2017;Strokova et al 2018;Funk et al 2019;Torres-Carrasco et al 2019;Augustyniak et al 2020b). In Funk et al (2019) analyzed micro-and nano-components' release from cementitious composites containing TiO 2 and SiO 2 NPs after freeze-thawing.…”

Section: Introductionmentioning

confidence: 99%

Investigating the release of ZnO nanoparticles from cement mortars on microbiological models

et al. 2021

View full text Add to dashboard Cite

Incorporating zinc oxide nanoparticles (ZnO NPs) into cement mortars may provide additional functions, e.g., self-cleaning and antibacterial or electroconductive ability. However, these NPs are also known for their potential toxicity. During the life cycle of a cement mortar, various abrasive forces cause the release of admixtures to the natural environment. The effect of the released NPs on model microorganisms has not been extensively studied. Previous studies have shown that nanomaterials may affect various microorganisms’ physiological responses, including changes in metabolic activity, biofilming, or growth rate. In this study, we have focused on evaluating the response of model microorganisms, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans, towards ZnO nanoparticles released from cement mortars in different deterioration scenarios. The addition of ZnO nanoparticles to cement mortars had a noticeable effect on impeding the strength development. We have also detected that depending on the deterioration scenario, the release of ZnO nanoparticles was varied. Our studies have also shown that even though the release of nanoform ZnO could be limited by poor dispersion or the used filtration technique, the eluates have caused slight but statistically significant changes in the physiological features of studied microorganisms showing relatively low toxicity.

show abstract

Critical aspects in the handling of reactive silica in cementitious materials: Effectiveness of rice husk ash vs nano-silica in mortar dosage

Cited by 40 publications

References 36 publications

The effects of calcium–silicate–hydrate (C–S–H) seeds on reference microorganisms

The effects of calcium–silicate–hydrate (C–S–H) seeds on reference microorganisms

Comparative Overview of the Performance of Cementitious and Non-Cementitious Nanomaterials in Mortar at Normal and Elevated Temperatures

Investigating the release of ZnO nanoparticles from cement mortars on microbiological models

Contact Info

Product

Resources

About