Determination of sulfate content in OPC and CSA …
Determination of sulfate content in OPC and CSA cement by sodium carbonate extraction method | Semantic Scholar. DOI: …
Utilization of waste-based sodium sulfates in alkali-
The purpose of this study is to investigate the use of waste-based sodium sulfate as an activator in an alkali-activated material. The precursor in this research is blast furnace …
Unlocking the potential of ordinary Portland cement …
An identical OPC was used in the mix design when needed: OPC for the main research, OPC2 for the limestone calcined clay cement (LC 3) system and OPC3 for the …
Sulfate attack and role of silica fume in resisting strength loss
For the OPC-45 mortar specimen, the most marked difference between sodium sulfate attack and magnesium sulfate attack was a visible loss of mass, as shown in Fig. 1, Fig. 3. The significant expansion of the OPC mortar specimen, and the consequent disintegration seems to be responsible for the considerable mass loss in sodium sulfate …
Improving the sulfate attack resistance of concrete …
MK replacement of the OPC showed improved sulfate resistance in sodium sulfate exposure at replacement rates of 5–25%; higher dosages resulted in better performance. In magnesium sulfate, sulfate resistance performance was more mixed …
Compressive strength of OPC concrete and RHA blended
The OPC concrete produced low compressive strength compared with RHA10 and RHA20 concrete when subjected to sodium sulfate, and the strength deteriorated after 90 days (see Fig. 1).
Effect of sodium sulfate on the hydration and mechanical
Zhao et al. [84] investigated the sodium sulfate at various content (0 %, 0.8 %, 2.4 % and 8 %) on the setting time of lime-activated slag binder and reported that the incorporation of sodium ...
The role of sulfate ions in tricalcium aluminate hydration: New
This paper focuses on the effects of sodium sulfate and potassium sulfate on the hydration mechanism and properties of calcium sulfoaluminate (CSA) cement based double liquid grouting materials ...
A Review of Durability and Strength Characteristics …
Using ground granulated blast furnace slag (GGBS) as an alternative to OPC requires its activation with high alkalinity compounds such as sodium hydroxide (NaOH), …
Effect of relative GGBS/fly contents and alkaline solution
For alkali-activated slag mortars submerged in sodium sulfate solution for one year, XRD analyses published in the literature showed the presence of quartz, C-A-S-H gel, and hydrotalcite, without ...
Ordinary Portland Cement
16.3.1 Materials and test specimens. Ordinary Portland Cement (OPC grade 53) manufactured by the Ultratech cement company from Gujarat, having a specific gravity of 3.15 g/cm 3, was used. Locally available 20 and 10-mm sized aggregates from around the Rajkot city area were used as coarse aggregates.
Resistance of concrete and mortar against combined
When OPC mortar is immersed for 616 days in a single sodium sulphate solution, more than a quarter of the initial mass of the specimen is lost due to cracking and spalling of the outermost layers. When OPC samples are immersed in a combined solution of sodium sulphate and sodium chloride for the same period, no mass is lost.
Influence of Titanium Dioxide Nanoparticles on the …
After immersion for 84 days at 25 °C, 12% OPC and 12% slag-blended mortars gained 3.01% and 1.41% mass, respectively, while 0% OPC and 0% slag-blended mortars …
Buildings | Free Full-Text | Review of Recent Developments
Nnaemeka and Singh indicated how kaolin affected the durability of fly ash-based GPC when exposed to a solution of sodium sulfate at a 5% concentration. The results show that, in comparison to traditional OPC concrete, geopolymer concrete generally exhibited superior resistance to chemical deterioration.
Sulfate determination: Ion chromatography
After centrifugation, serum samples are generally diluted 10-fold and urine samples 100-fold with the sodium bicarbonate eluent. To measure the performance of the chromatographic system for determining sulfate in physiological fluids, ... Determination of sulfate content in OPC and CSA cement by sodium carbonate extraction method. 2021 ...
Ion chromatography determination of chloride and sulphate …
The contents of chlorine and sulphur species in commercial portland cement were determined by a two-step sample preparation procedure. The first step was carried out by means of sodium carbonate and peroxide fusion, followed by a second step of electrodialytic neutralisation of the resulting solution. The chloride and sulphate contents …
Resistance of concrete and mortar against combined attack …
Semantic Scholar extracted view of "Resistance of concrete and mortar against combined attack of chloride and sodium sulphate" by Mathias Maes et al. Skip to search form Skip to main ... ions on chloride penetration has not been investigated in detail. In this research, standard ordinary portland cement (OPC) mortar and partial cement ...
A Review of Durability and Strength Characteristics of Alkali …
Using ground granulated blast furnace slag (GGBS) as an alternative to OPC requires its activation with high alkalinity compounds such as sodium hydroxide (NaOH), sodium sulfate (Na 2 SO 3), sodium carbonate (Na 2 CO 3), or combination of these compounds such as NaOH and Na 2 SO 3. The mechanism of alkali-activation is still not …
Impact of sulfoaluminate cement modification on
In addition, Cui et al. [37] demonstrated that the complete replacement of OPC with CSA improved the sulfate resistance of RPC exposed to sodium sulfate solution. These studies confirm that the use of CSA in UHPC can effectively improve some important properties. In contrast, the present study conducted a previously unexplored …
Corrosion behavior of steel reinforcement in concrete …
Magnesium sulfate and sodium sulfate concentrations each of 2.5% and 5% (by mass of water) were added along with above concentrations of sodium chloride for the preparation of composite solutions. ... Half-cell potential vs. w/c ratio for OPC exposed to sodium chloride solutions. Download : Download full-size image; Fig. 12.
Sodium Sulfate | Formula, Properties & Application
The sodium sulfate molecule consists of two sodium atoms (Na), one sulfur atom (S), and four oxygen atoms (O). The molecule adopts a highly symmetrical structure, which contributes to its properties and behavior in different applications. Solubility: It is readily soluble in water but not in ethanol.
Immobilisation matrices for intermediate level nuclear …
Request PDF | Immobilisation matrices for intermediate level nuclear wastes using sulphate activated BFS/OPC and PFA/OPC composite cements | The highly alkaline pore solution of ordinary Portland ...
[PDF] Influence of SO 4 2- Ions Concentration on Sulfate …
This paper was conducted to evaluate the durability of cement mortars exposed to varying concentrations of sodium sulfate for up to 540 days. Three types of cement mortars, namely OPC, SRC and SGC, were exposed to four sodium sulfate solutions with concentrations of 4225, 8450, 16900 and 33800 ppm of ions at ambient temperature. …
Durability of geopolymer materials in sodium and magnesium sulfate
1. Introduction. Sulfate attack is an important durability and serviceability concern for geopolymer materials used in construction. Previous experience with Portland cement and blended cement concretes showed cases of concrete deterioration when exposed to sulfate attack in the environment [1], [2], [3].Studies of the sulfate attack on …
Utilizations of preheated flue gas desulfurization gypsum and sulfate …
Current study proposes an effective way to modify the properties of super-sulfated cement (SSC) paste and mortar with preheated flue gas desulfurization (FDG) gypsum at different temperatures and durations, and different sulfate compositions. Preheated FGDs with temperatures between 25 and 150 °C and durations between 0 …
Durability of self-consolidating concrete to different
This study investigates the durability of a wide scope of self-consolidating concrete (SCC) mixture designs to sodium sulfate attack. The mixture design variables included the type of binder (single, binary, ternary and quaternary), air-entrainment, sand-to-aggregate ratio and hybrid fibre reinforcement. Since current standard test methods (e.g. …
Materials | Free Full-Text | A Review of Durability and …
Using ground granulated blast furnace slag (GGBS) as an alternative to OPC requires its activation with high alkalinity compounds such as sodium hydroxide (NaOH), sodium sulfate (Na 2 SO 3), sodium carbonate (Na 2 CO 3), or combination of these compounds such as NaOH and Na 2 SO 3. The mechanism of alkali-activation is still not …
Sodium silicate effect on setting properties, strength behavior and
This study offers the effect of sodium silicate (SS) as an accelerator on early age mechanical and microstructure properties of CCB. SS-based admixture was used for a dosage of 0.5, 1 and 1.5 wt% in CCB that contains 25 wt% ordinary Portland cement OPC and 75 wt% coal fly ash.
Sulfate attack on alkali-activated slag concrete
After 12 months of exposure to the sodium sulfate solution, the strength decrease was up to 17% for AAS concrete and up to 25% for ordinary Portland cement …
Fresh mechanical and durability properties of alkali
Normal concrete (OPC) suffered higher deterioration than geo-polymer concrete due to sodium sulfate environment with reduction of volume by 15% compared to 13% and 12% of slag and fly-ash based geopolymer concrete respectively.
