Performance of self-compacting concrete containing nano clay at elevated temperatures and MgSO<sub>4</sub> attack

Alani, Nibras Y.; Al-Jumaily, Ibrahim A. S.; Hilal, Nahla

doi:10.1080/19648189.2022.2121766

Cited by 2 publications

(1 citation statement)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Meanwhile, the density, compressive and splitting tensile strengths of all SCC mixes decreased after periods of exposure to both H 2 SO 4 and MgSO 4 solution attacks. Nibras Y. Alani et al [15] investigated the performance of SCC containing nano clay at elevated temperatures and exposed to a MgSO 4 attack, and pointed out that the nano clay incorporating SCC specimens possessed higher durability properties. With respect to MOC, so far, the effects of a high salt environment, high heat environment, dry-wet cyclic environment and long-term indoor environment on the deterioration properties of MOC materials have also been reported [16][17][18][19].…”

Section: Introductionmentioning

confidence: 99%

Study on the Deterioration Mechanism of Magnesium Oxychloride Cement under an Alkaline Environment

An,

Chang,

Yan

et al. 2023

Materials

View full text Add to dashboard Cite

The deterioration process and deterioration mechanism of magnesium oxychloride cement (MOC) in an alkaline environment were studied using a scanning electron microscope (SEM), an X-ray diffractometer (XRD), a Fourier transform infrared spectrometer (FT-IR) and a micro-electro-hydraulic servo pressure testing machine to investigate the effects of soaking time in 10 wt.% NaOH solution on the macro- and micro-morphology, phase composition and compressive strength of MOC samples. The results show that the deterioration of MOC samples under an alkaline environment is mainly caused by the alkaline environment providing more OH− ions, which can react with 5Mg(OH)2·MgCl2·8H2O (P 5) in the sample. The resulting reaction gives rise to a faster decomposition of 5Mg(OH)2·MgCl2·8H2O (P 5) and a substantial reduction in the strength of the sample, and finally leads to a gradual deterioration of MOC samples. Meanwhile, immersion time exhibits a significant effect on MOC samples. The extension of immersion time coincides with more OH− ions entering the sample, and the greater presence of OH ions increases the likelihood that more P 5 will produce a hydrolysis reaction, further resulting in the increased deterioration of the sample. After soaking for 6 h in alkaline media, the main phase composition of the surface layer of an MOC sample changes to MgO and Mg(OH)2, and its microscopic morphology is also dominated by round sheets, giving rise to a sharp decrease in its compressive strength (52.2%). When the immersion time is prolonged to 72 h, OH− ions have already immersed into the inner core of the sample, causing the disappearance of P 5 from the whole sample. At the same time, both the surface and inner core of the sample exhibit a disc-shaped morphology, and chalking phenomena also appear on the surface of the sample. This reduces the compressive strength of the sample to 13.5 MPa, only 20% of its compressive strength in water. The compressive strength of the sample after 120 h of immersion is as low as 8.6 MPa, which is lower than that of the sample dipped in water for 21 days (9.5 MPa). As a result, the MOC samples studied in alkaline environments exhibit a faster deterioration rate, mainly because of a faster hydrolysis reaction by P 5, caused by more OH− ions.

show abstract

Section: Introductionmentioning

confidence: 99%

Study on the Deterioration Mechanism of Magnesium Oxychloride Cement under an Alkaline Environment

An,

Chang,

Yan

et al. 2023

Materials

View full text Add to dashboard Cite

show abstract

Research on Enhancing the Corrosion Resistance of Concrete in a MgSO4 Corrosive Environment Using CTF Synergist

Wang,

Qiao,

Zhang

et al. 2024

KSCE J Civ Eng

View full text Add to dashboard Cite

Performance of self-compacting concrete containing nano clay at elevated temperatures and MgSO₄ attack

Cited by 2 publications

References 30 publications

Study on the Deterioration Mechanism of Magnesium Oxychloride Cement under an Alkaline Environment

Study on the Deterioration Mechanism of Magnesium Oxychloride Cement under an Alkaline Environment

Research on Enhancing the Corrosion Resistance of Concrete in a MgSO4 Corrosive Environment Using CTF Synergist

Contact Info

Product

Resources

About

Performance of self-compacting concrete containing nano clay at elevated temperatures and MgSO4 attack

Cited by 2 publications

References 30 publications

Study on the Deterioration Mechanism of Magnesium Oxychloride Cement under an Alkaline Environment

Study on the Deterioration Mechanism of Magnesium Oxychloride Cement under an Alkaline Environment

Research on Enhancing the Corrosion Resistance of Concrete in a MgSO4 Corrosive Environment Using CTF Synergist

Contact Info

Product

Resources

About

Performance of self-compacting concrete containing nano clay at elevated temperatures and MgSO₄ attack