Internal and external sources of sulfate ions in portland cement mortar: two types of chemical attack

Ouyang, C.; Nanni, Antonio; Chang, Wen F.

doi:10.1016/0008-8846(88)90092-0

Cited by 123 publications

(56 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Decreasing the overall tricalcium aluminate content, which reacts with water and sulfate to form ettringite, can result in improved resistance to sulfate attack. Several studies have shown that a lower tricalcium aluminate content can lead to improved resistance (Monteiro and Kurtis, 2003;Ouyang et al, 1998;Verbeck, 1967). The impact of reducing the tricalcium aluminate content is widely recognised and sulfate-resisting cements have been subsequently devised (Type V from ASTM C150/C150M-12 (ASTM, 2012) and the CEM I-SR series from BS EN 197-1:2011(BSI, 2011).…”

Section: Precipitation Of Ettringitementioning

confidence: 99%

Current knowledge of external sulfate attack

Whittaker¹,

Black²

2015

Advances in Cement Research

View full text Add to dashboard Cite

This paper offers an update of the current understanding of sulfate attack, with emphasis on the sulfates present in an external water source percolating through, and potentially reacting with, the cement matrix. The paper considers the explanations put forward to explain sulfate attack, both from a chemical and microstructural perspective.Similarly, this paper reviews work on the physical damage caused by the precipitation of sulfate salts in porous materials. With the increased use of binary and ternary blends, this paper also considers the impact of binder composition on sulfate resistance, and similarly reviews how the nature of the sulfate species can affect the nature and extent of any deterioration. This then leads on to the important consideration of differences between field-and lab-based studies, reviewing the effect of various experimental parameters on sulfate resistance. This latter topic is of great importance to anyone who wishes to carry out such experiments.

show abstract

Section: Precipitation Of Ettringitementioning

confidence: 99%

Current knowledge of external sulfate attack

Whittaker¹,

Black²

2015

Advances in Cement Research

View full text Add to dashboard Cite

show abstract

“…The iron-and aluminium-containing hydrates of Portland cement dissolve slower and at lower pH values than calcium hydrates (Beddoe and Dorner, 2005), so the addition of supplementary cementitious materials (SCMs) to Portland cement has been tested and shown to improve the cement's acid resistance by lowering the calcium content and decreasing porosity (Al-Akhras, 2006;Bakharev 2005;Bakharev et al, 2002;Lee et al, 2005;Ouyang et al, 1988). In the case of attack by sulfate ions, SCMs also help to preserve matrix integrity since they do not form expanding reaction products.…”

Section: Introductionmentioning

confidence: 99%

Acid resistance of calcium aluminate cement–fly ash F blends

Pyatina

Sugama

2016

Advances in Cement Research

View full text Add to dashboard Cite

The short-term resistance to sulfuric acid at 90°C of four calcium aluminate cement (CAC)-fly ash class F (FAF) blends activated with sodium metasilicate (thermal shock resistant cements (TSRCs)), cured at 300°C, was compared to that of a calcium phosphate cement (CPC) (CAC-FAF blend activated with sodium hexametaphosphate) and a Portland cement class G/silica blend. The mechanical properties and compositions of the acid-exposed samples were evaluated by measuring their compressive strength and by means of x-ray diffraction, μEDX (energy-dispersive x-ray spectrometry), thermogravimetric and Fourier transform infrared analyses. All calcium-containing hydrates were sensitive to the conditions of acid exposure. In the TSRC blends, these hydrates included hydrogrossular, feldspar family minerals and zeolites; in CPC, feldspar minerals and phosphate phases; and in the class G/silica blend, portlandite and tobermorite.Crystalline calcium sulfates formed in the acid-exposed surfaces with the exception of the most aluminium-rich TSRC samples where only potassium(sodium) aluminium sulfate, alunite, was detected. This sample underwent the least changes in weight, compressive strength and had the lowest sulfur permeation into the sample core. Calcium sulfates precipitated on sample surfaces limited sulfur penetration into the core of calcium-rich TSRC, CPC and G/silica blends.

show abstract

“…When pozzolanic materials are combined with PC, the normal Portland cement hydration reaction takes place but other chemical reactions also occur. The pozzolanic reaction, reactive siliceous and aluminous phases react with calcium hydroxide (Ca(OH) 2 emissions in cement production, as the amount of Portland cement can be reduced in the concrete [6]. The replacement of PC with pozzolanic materials reduces the overall CO 2 footprint of the material.…”

mentioning

confidence: 99%

Study on the Expansion of a Cement-Based System Containing Sap Polymer and Supplementary Cementing Materials

Ávalos-Rendón¹,

Mendoza²

2017

MSA

View full text Add to dashboard Cite

In this paper, the addition of admixed superabsorbent polymer (SAP) improved the microstructure and durability-related properties in a cement-based system with supplementary materials. This is an important issue in real construction projects when good durability properties are required. This study investigates the effect of SAP on the systems using cement replacement by fly ash and silica fume considering the strength properties and durability properties of paste under sulfate attack of cement-based system. The replacement considered in the study was of 10% silica fume and 20% fly ash in each case, the dosage of SAP was 0.25% of the total amount of cementitious material. The results showed that the addition of SAP in the cement-based system improved the compressive strength and reduced expansion to sulfate attack. Scanning electron micrographs showed that utilization of fly ash with silica fume and silica fume with SAP resulted in a much denser microstructure, thereby, leading to an increase in compressive strength and lower expansion under sulfate attack.

show abstract

Internal and external sources of sulfate ions in portland cement mortar: two types of chemical attack

Cited by 123 publications

References 2 publications

Current knowledge of external sulfate attack

Current knowledge of external sulfate attack

Acid resistance of calcium aluminate cement–fly ash F blends

Study on the Expansion of a Cement-Based System Containing Sap Polymer and Supplementary Cementing Materials

Contact Info

Product

Resources

About