scholarly journals The Impact of Aluminum- and Iron-Bearing Admixtures on the Resistance of Portland Cement Mortars to Alkali-Silica Reaction and Sulfate Attack

2015 ◽  
Vol 06 (06) ◽  
pp. 539-548
Author(s):  
Alexey Brykov ◽  
Anna Anisimova ◽  
Natalya Rozenkova ◽  
Mohammed Hadi ◽  
Maxim Mokeev
Keyword(s):  
Portland Cement ◽  
Sulfate Attack ◽  
Alkali Silica Reaction ◽  
Cement Mortars ◽  
The Impact ◽  
Iron Bearing

scholarly journals Expansion Behavior of Portland Cement Mortars under Sulfate Attack

2007 ◽  
Vol 353-358 ◽  
pp. 2577-2580
Author(s):  
Jian Kang Chen ◽  
Min Qiang Jiang ◽  
Ding Yi Yang
Keyword(s):  
Portland Cement ◽  
Sulfate Attack ◽  
Expansion Behavior ◽  
Cement Mortars

scholarly journals Evaluation of external sulfate attack (Na2SO4 and MgSO4): Portland cement mortars containing fillers

2020 ◽  
Vol 13 (3) ◽  
pp. 644-655 ◽  
Author(s):  
D. J. DE SOUZA ◽  
M. H. F. MEDEIROS ◽  
J. HOPPE FILHO
Keyword(s):  
Portland Cement ◽  
Linear Expansion ◽  
Sulfate Attack ◽  
Hardened Cement ◽  
X Ray Diffraction ◽  
Limestone Filler ◽  
Sulfate Ions ◽  
X Ray ◽  
Cement Mortars ◽  
Physical And Chemical

Abstract Sulfate attack is a term used to describe a series of chemical reactions between sulfate ions and hydrated compounds of the hardened cement paste. The present study aims to evaluate the physical (linear expansion, flexural and compressive strength) and mineralogical properties (X-ray diffraction) of three different mortar compositions (Portland Cement CPV-ARI with limestone filler and, with a quartz filler, in both cases with 10% replacement of the cement by weight) against sodium and magnesium sulfate attack (concentration of SO4 2- equal to 0.7 molar). The data collected indicate that the replacing the cement by the two fillers generate different results, the quartz filler presented a mitigating behaviour towards the sulfate, and the limestone filler was harmful to Portland cement mortars, in both physical and chemical characteristics.

Differentiating seawater and groundwater sulfate attack in Portland cement mortars

2006 ◽  
Vol 36 (12) ◽  
pp. 2132-2137 ◽  
Author(s):  
Manu Santhanam ◽  
Menashi Cohen ◽  
Jan Olek
Keyword(s):  
Portland Cement ◽  
Sulfate Attack ◽  
Cement Mortars

Effect of Electron Beam and Heat Treatment on the Reactivity of Aggregates and Mineral Additives towards Alkali-Silica Reaction in Portland Cement Compositions

2020 ◽  
Vol 992 ◽  
pp. 3-8
Author(s):  
Aleksei B. Brykov ◽  
S.V. Mjakin ◽  
M.M. Sychov
Keyword(s):  
Heat Treatment ◽  
Electron Beam ◽  
Portland Cement ◽  
Absorbed Dose ◽  
Alkali Silica Reaction ◽  
Hydroxyl Groups ◽  
Treatment Results ◽  
Cement Mortars ◽  
Mineral Additives ◽  
Similar Processing

Electron beam (EB) and heat treatment of silica-containing aggregates and mineral additives for Portland cement mortars is shown to affect their activity in alkali-silica reaction (ASR) damaging concrete structures. In the case of ordinary mortar based on the sand free of alkali-reactive inclusions, both heating to 900°C and EB processing result in a significant increase of reactivity growing with the absorbed dose in the range from 100 to 600 kGy and correlating with the increase in the content of acidic hydroxyl groups on the surface. For sand with reactive chalcedony inclusions, EB treatment results in the growth of their reactivity while heating provides its significant decrease. In case of mineral additives such as silica fume and metakaolin known as very effective ASR-inhibitors, similar processing leads to the increase of their activity in mitigation of ASR. The observed effect is promising for simulation of expansion processes caused by ASR and enhancement of concrete structure resistance to alkali destruction during exploration.

scholarly journals Evaluation of external sulfate attack (Na2SO4 and MgSO4): Portland cement mortars containing siliceous supplementary cementitious materials

2020 ◽  
Vol 13 (4) ◽  
Author(s):  
Diego Jesus de Souza ◽  
Marcelo Henrique Farias de Medeiros ◽  
Juarez Hoppe Filho
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Cementitious Materials ◽  
Sulfate Attack ◽  
Supplementary Cementitious Materials ◽  
Hardened Cement ◽  
X Ray Diffraction ◽  
Sulfate Ions ◽  
Cement Mortars ◽  
Physical And Chemical

ABSTRACT: Sulfate attack is a term used to describe a series of chemical reactions between sulfate ions and hydrated compounds of the hardened cement paste. The present study aims to evaluate the physical (linear expansion, flexural and compressive strength) and mineralogical properties (X-ray diffraction) of three different mortar compositions (Portland Cement CPV-ARI containing silica fume and rice husk ash, in both cases with 10% replacement of the cement by weight) against sodium and magnesium sulfate attack (concentration of SO42- equal to 0.7 molar). The data collected indicate that the replacing the cement by the two siliceous supplementary cementitious materials (SCMs) generate similar results, both SCMs were able to mitigate the effects of the sodium sulfate attack in both physical and chemical characteristics, however, both materials increase the deterioration (i.e. compressive strength) when exposed to MgSO4 solution.

scholarly journals Alkali-silica reaction (ASR) - Investigation of crystallographic parameters of natural sands by backscattered electron diffraction

2021 ◽  
Vol 14 (3) ◽  
Author(s):  
Kleber Franke Portella ◽  
Leonardo Evangelista Lagoeiro ◽  
Jeferson Luiz Bronholo ◽  
Dayane de Cristo Miranda ◽  
Mariana D’Orey Gaivão Portella Bragança ◽  
...  
Keyword(s):  
Electron Diffraction ◽  
Portland Cement ◽  
Alkali Silica Reaction ◽  
X Ray ◽  
Electron Backscattering ◽  
Electron Backscattering Diffraction ◽  
Cement Mortars ◽  
Backscattered Electron ◽  
Crystallographic Planes ◽  
Mortar Bar

abstract: This study involved analyzing several natural sands to ascertain the possible causes for distress due to ASR. The analyses were performed using the following techniques: X-ray diffractometry, accelerated mortar bar tests (AMBT), electron backscattering diffraction and elementary chemistry analyses, by FEG-SEM/EBSD/EDS. These experiments allowed identifying the presence of several mineral composites (such as microcline, anorthite, among others), as well as the microstructural-crystallographic planes of quartz (such as the Dauphiné type). From the results it could be inferred that the multiple techniques used, especially the FEG-SEM / EBSD, proved to be promising in the analysis of the ASR potential of sands for use in Portland cement mortars and concretes.

Effect of S2Cl2Addition on the Sulfate Attack of Hydrated Portland Cement

2009 ◽  
Vol 51 (3) ◽  
pp. 110-115
Author(s):  
H. Aygül Yeprem ◽  
Selahattin Gökmen
Keyword(s):  
Portland Cement ◽  
Sulfate Attack
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