Sulfate resistance of cement-reduced eco-friendly concretes

Mittermayr, Florian; Rezvani, Moien; Baldermann, Andre; Hainer, Stefan; Breitenbücher, Peter; Juhart, Joachim; Graubner, Carl‐Alexander; Proske, Tilo

doi:10.1016/j.cemconcomp.2014.09.020

Cited by 47 publications

(11 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For C-A-S-H phases basically the same uptake mechanisms of Me ions have been considered, but experimental studies are still scarce and/or lack control of the nature of the precipitates. Zhao et al [29] have recently shown that synthetic aluminium-and sucrose-substituted tobermorite (Ca 5 [44] have presented removal efficiencies for Cd 2þ , Zn 2þ , Pb 2þ , and Cr 3þ ions of 99.96% or higher after reaction with freshly prepared C-S-H, and Giergiczny and Król [45] have reported very high immobilization degrees for Pb 2þ , Cu 2þ , Zn 2þ , Cr 6þ , Cd 2þ , and Mn 2þ ions, from * 86 to 99.99%, after reaction with mortars made of OPC and different levels of GGBFS and fly ash. The principle mechanism proposed for the removal of these Me ions by C-A-S-H or C-S-H was structural incorporation, though co-precipitation of discrete Me-oxyhydrates was frequently observed [29,44,45], suggesting that the removal mechanism(s) are more complex than previously thought.…”

Section: Removal Of Heavy Metals By Calciumaluminium-silicate-hydratesmentioning

confidence: 99%

“…Importance of calcium-aluminium-silicatehydrate phases Aluminium-substituted calcium-silicate-hydrates (C-A-S-H) are of great technological importance, because they represent the main hydration product in ordinary Portland cement (OPC) and thus significantly contribute to the physicochemical characteristics, mechanical properties, and durability of hardened cementitious materials, such as concrete and shotcrete [1][2][3][4][5][6][7]. Apart from being the most important construction material of our time, concrete is nowadays applied in special wastewater treatment technologies and in the remediation of (sub)soil structures that are contaminated with hazardous components, like toxic heavy metal ions [4,[8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Removal of heavy metals (Co, Cr, and Zn) during calcium–aluminium–silicate–hydrate and trioctahedral smectite formation

et al. 2019

Self Cite

View full text Add to dashboard Cite

Hydrated aluminosilicates were synthesized with and without aqueous heavy metals (Me), such as cobalt (Co), chromium (Cr), and zinc (Zn), by a sol-gel process at different initial molar ratios of Ca/(Si ? Al) (0.6-1.6) and Me/Si (0.0-2.0), and constant Al/Si ratio (0.05) using equilibrium-approaching experiments. The chemical composition of the reactive solutions during aluminosilicate precipitation and maturation was monitored by ICP-OES. The mineralogy, nanostructure, and chemical composition of the precipitates were studied by XRD and high-resolution TEM. At Me/Si ratios B 0.2, calcium-aluminium-silicate-hydrates (C-A-S-H) with a defect 14 Å tobermorite-like structure formed, whereas at a Me/Si ratio of 2.0, either trioctahedral Co-and Zn-smectite or amorphous Cr gels precipitated, independent of the initial Ca/(Si ? Al) ratio used for gel synthesis. The immobilization capacities for Co 2þ , Cr 3þ , and Zn 2þ by C-A-S-H, Cr gel, and trioctahedral smectite are 3-40 mg/g, 30-152 mg/g, and 122-141 mg/g, respectively. The immobilization mechanism of heavy metals is based on a combination of isomorphous substitution, interlayer cation exchange, surface (ad)sorption, and surface precipitation. In engineered systems, such as underground concrete structures and nuclear waste disposal sites, hydrated aluminosilicates should exhibit a high detoxication potential for aqueous heavy metals.

show abstract

Section: Removal Of Heavy Metals By Calciumaluminium-silicate-hydratesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Removal of heavy metals (Co, Cr, and Zn) during calcium–aluminium–silicate–hydrate and trioctahedral smectite formation

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…The authors attributed the compressive strength increase to biocementation. Mittermayr et al, [68] showed that the increase in compressive strength could be as a result of densification of cementitious matrix at microstructural level. Najjar et al, [69] in their work reported that ingress of sulfate ions into the concrete matrix triggers the formation of expansive products that fills the pores and voids leading to the densification of microstructure during the initial exposure of concrete to sulfate rich areas.…”

Section: Chemical Sulphate Attack 311 Compressive Strengthmentioning

confidence: 99%

Use of Bacillus Species Bacteria in Protecting the Concrete Structures from Sulphate Attack- A Review

et al. 2019

View full text Add to dashboard Cite

Deleterious ions in the environment such as sulfates may degrade the concrete structures. The interaction of cement hydration products with these destructive agents contributes to severe durability threat of the concrete structures. External sulfate attack is well-known for causing permanent changes in concrete. Microbially induced calcium carbonate (MICP) precipitation has been considered as a unique technique in enhancing the durability properties of concrete. This review paper discusses the possibility of bio-deposition from MICP process as a barrier in microbial treated concrete against the penetration of sulfate ions in a sulfate-rich environment. The effect associated with chemical and physical sulfate attack is discussed in line with the mechanical properties of cement such as compressive strength whereas microscopic evaluation is based on scanning electron microscopy studies. The shortcomings associated with sulfate ions in cement-based materials and the positive effects of incorporating bacillus species bacteria in sulfate rich areas is discussed. This review found that, MICP can significantly reduce the ingress of sulfate ions in cement-based materials, which results in improving the mechanical properties of the cement mortar/concrete.

show abstract

“…In addition, by providing SO 4 2-the precipitation of sulfate minerals such as gypsum (CaSO 4 · 2H 2 O) and ettringite ((CaO) 3 · Al 2 O 3 · (CaSO 4 ) 3 · 32H 2 O) is promoted [17,18]. The formation of gypsum and ettringite is well known to cause intense microstructural damage by high crystallization pressures [19][20][21]. (iv) As the interstitial solution pH of the initially damaged concrete decreases progressively, different strains of bacteria colonize the pores of the concrete, with Acidithiobacillus thiooxidans being the most aggressive one [10].…”

Section: Introductionmentioning

confidence: 98%

Microbiologically induced concrete corrosion: A case study from a combined sewer network

Grengg

Mittermayr

Baldermann

et al. 2015

Cement and Concrete Research

134

View full text Add to dashboard Cite

In this study, a strongly deteriorated concrete-based sewer system was investigated by using a multi proxy approach based on gaseous, hydro-geochemical, microbiological, mineralogical and mechanical analyses. Therefore, gas, liquid, and solid samples were taken throughout the entire sewer system. Long term measurements of gaseous hydrogen sulfide (H 2 S) within the sewer atmosphere yielded concentrations up to 367 ppm. Interstitial fluids, extracted from deteriorated concrete by squeezing, contained sulfate (SO 4 2− ) concentrations of up to 104 g l −1 at strong acidic conditions (0.7 N pH N 3.1) and are close to the saturation state of gypsum. This sulfuric acid attack is indicative for a well-established biofilm containing sulfide oxidizing bacteria (SOB), which was analyzed to consist mainly of Acidithiobacillus thiooxidans. The micro-structure of the attacked concrete displays a progressing alteration zone, which is caused by microbially induced concrete corrosion (MICC), with a suggested pH gradient from about 13 to b 1, from the intact inner concrete zone to the outermost heavily deteriorated concrete. Calcium sulfate minerals such as gypsum (CaSO 4 · 2H 2 O), bassanite (CaSO 4 · 1/2H 2 O) and anhydrite (CaSO 4 ) are abundant in the altered concrete, which were formed from the dissolution of the cement phases and Ca-bearing aggregates. Remarkably high corrosion rates of different precast concrete manholes were quantified to reach values greater than 1 cm yr −1 , despite the fact that C 3 A-free cement, fly ash and a w/c of~0.35 was used.

show abstract

Sulfate resistance of cement-reduced eco-friendly concretes

Cited by 47 publications

References 57 publications

Removal of heavy metals (Co, Cr, and Zn) during calcium–aluminium–silicate–hydrate and trioctahedral smectite formation

Removal of heavy metals (Co, Cr, and Zn) during calcium–aluminium–silicate–hydrate and trioctahedral smectite formation

Use of Bacillus Species Bacteria in Protecting the Concrete Structures from Sulphate Attack- A Review

Microbiologically induced concrete corrosion: A case study from a combined sewer network

Contact Info

Product

Resources

About