The physical and chemical effects of long-term sulphuric acid exposure on hybrid modified cement mortar

Li, Gengying; Guang-jing, Xiong; Lu, Yao; Yin, Yuan‐Qi

doi:10.1016/j.cemconcomp.2009.02.014

Cited by 24 publications

(10 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous studies have discussed the mechanism of acid attack (i.e., acid corrosion) of CBMS. In the case of sulfuric acid, the deterioration of CBMS exposed to acid is mainly due to the presence of H + and SO 4 2− ions, which can lead to the dissolution of hydration products and the formation of expansive compounds [63,64,65,66]. The nanomaterial, such as calcined nanokaolinite clay (NKC), has been reported by Fan et al [67] to improve the resistance of the cement mortar to acid solution exposure.…”

Section: Nanotechnology For Cbms To Overcome Chemical Deteriorationsmentioning

confidence: 99%

Nanotechnology in Cement-Based Materials: A Review of Durability, Modeling, and Advanced Characterization

AlShareedah

et al. 2019

Nanomaterials

110

View full text Add to dashboard Cite

In the context of increasing applications of various nanomaterials in construction, this work reviews the renewed knowledge of nanotechnology in cement-based materials, focusing on the relevant papers published over the last decade. The addition of nanomaterials in cement-based materials, associated with their dispersion in cement composites, is explored to evaluate their effects on the resistance of cement-based materials to physical deteriorations, chemical deteriorations, and rebar corrosion. This review also examines the proposed nanoscale modeling of interactions between admixed nanomaterials and cement hydration products. At last, the recent progress of advanced characterization that employs techniques to characterize the properties of cement-based materials at the nanoscale is summarized.

show abstract

Section: Nanotechnology For Cbms To Overcome Chemical Deteriorationsmentioning

confidence: 99%

Nanotechnology in Cement-Based Materials: A Review of Durability, Modeling, and Advanced Characterization

AlShareedah

et al. 2019

Nanomaterials

110

View full text Add to dashboard Cite

show abstract

“…The W2 treatment worked more efficiently at early ages, while the effect of W3 treatment was more significant at 28 days. The reason was that the osmotic pressure increased with the viscosity of waterglass solution which increased with the modulus [54]. Therefore, waterglass with modulus of 3 could not deeply penetrate into concrete as waterglass with modulus of 2 at early ages.…”

Section: Interactions Between Waterglass and Cement Pastementioning

confidence: 99%

“…presents the FT-IR spectra over the range 2000 -400cm-1 for surface layers of the paste samples after different treatments. For the UNTR sample, the two main bands at 1430 cm -1 and 970 cm -1 are typical bands assigned to asymmetric stretching vibrations (v 3 ) of CO 3 2− and Q 2 (Si-O) stretching vibrations respectively[23,[27][28][29]. Weak shoulders at 875 cm −1 and 1640 cm −1 are caused by the out-of-plane bending vibrations (v 2 ) of CO 3 2− and bending vibrations of (O-H)[29].…”

mentioning

confidence: 99%

Interactions between inorganic surface treatment agents and matrix of Portland cement-based materials

Pan

Shi

et al. 2016

Construction and Building Materials

View full text Add to dashboard Cite

Magnesium fluorosilicate, waterglass, sodium fluorosilicate, and combination of waterglass and sodium fluorosilicate were used as surface treatment agents and their interactions with the Portland cement hydrates were studied. Thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FT-IR) were employed to analyze the phase changes in the hardened cement pastes after surface treatments. A scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) analysis was adopted to examine the changes in morphologies and chemical compositions. The TGA and FT-IR results showed that the inorganic surface treatments could reduce the content of Ca(OH) 2 in the surface layer of hardened cement, whereas the amount of calcium silicate hydrate (C-S-H) and silica gel increased. Combined treatment with waterglass and sodium fluorosilicate could generate more gel products, and made the sample surface denser than other treatments used in this work, because sodium fluorosilicate could accelerate the hardening of waterglass, and both waterglass and sodium fluorosilicate could reacte with cement hydrates respectively.

show abstract

“…Many research studies have examined the microstructure of cementitious materials subjected to sulphuric acid [13][14][15][16][17][18][19] . The main focus of the microstructural analysis in these studies has been on the formation of gypsum and/or ettringite in different areas and crack and micro crack formation and their patterns as it can explain changes of mechanical and structural properties of concrete.…”

Section: Introductionmentioning

confidence: 99%

Comparative Study between Microstructure of a Novel Durable Concrete and Normal Concrete Subjected to Harsh Environments

Salek

Samali

Murphy

et al. 2016

Proceedings of the 9th International Conference on Fracture Mechanics of Concrete and Concrete Structures

View full text Add to dashboard Cite

Degradation of concrete members exposed to aggressive sulphuric acid environments is a key durability issue that affects the life cycle performance and maintenance costs of vital civil infrastructures [1]. Groundwater, chemical waste, sulphur bearing compounds in backfill, acid rain in industrial zones and biogenic acid in sewage systems are the main sources of sulphuric acid affecting concrete structures. In this research, microstructures of a novel acid resistant concrete (ARC) and a type of conventional concrete (CC), as the reference, have been studied in the laboratory subjected to accelerated testing. For this purpose, ARC and CC, were immersed in 7% (by volume) sulphuric acid solution. Mechanical properties of both concretes as well as their microstructures were examined after 28 days of curing and then after two, four and eight weeks of exposure to acid. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Xray diffraction (XRD) and X-ray mapping (XRM) were employed to analyse the microstructure of concretes before and after exposure to acidic environment. The results of this analysis revealed interesting facts about the mechanism of sulphur penetration in both concrete samples. In addition, they showed differences in the crack locations and propagation patterns and in interfacial transition zones (ITZ) of concretes, particularly after acid exposure. These changes of microstructures, as was proved in experimental tests, could significantly contribute to changing the ductility of the concretes in modulus of rupture (MOR) test.

show abstract

The physical and chemical effects of long-term sulphuric acid exposure on hybrid modified cement mortar

Cited by 24 publications

References 9 publications

Nanotechnology in Cement-Based Materials: A Review of Durability, Modeling, and Advanced Characterization

Nanotechnology in Cement-Based Materials: A Review of Durability, Modeling, and Advanced Characterization

Interactions between inorganic surface treatment agents and matrix of Portland cement-based materials

Comparative Study between Microstructure of a Novel Durable Concrete and Normal Concrete Subjected to Harsh Environments

Contact Info

Product

Resources

About