Hydration of ordinary Portland cement and calcium sulfoaluminate cement blends

Trauchessec, Romain; Mechling, Jean-Michel; André, Luc; Roux, André Le; Rolland, Bruno Le

doi:10.1016/j.cemconcomp.2014.11.005

Cited by 203 publications

(87 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Calcium sulfoaluminate (CSA) cement is low-carbon cement, possessed with high early strength, good permeability, and improved durability [13][14][15]. More importantly, its pore solution is less alkaline than Portland cement, and CH is absent from the hydration products [16]; therefore, it has the potential to produce high-performance GFRC with improved durability properties. Many research studies have been done to investigate the microstructural features and durability of GFRC modified by CSA cement (CSA/GFRC).…”

Section: Introductionmentioning

confidence: 99%

Durability of GFRC Modified by Calcium Sulfoaluminate Cement under Elevated Curing Temperatures

Song

Dou

2019

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

CSA/GFRC is an advanced composite material possessed with great ductility and durability. However, its bending performance and fibre condition, as well as intrinsic microstructural changes, under elevated temperature have not been understood so far. XRD was applied in this study to investigate the hydration mechanism of CSA cement under 50°C, 70°C, and 80°C. Bending performance was carried out to test the toughness of CSA/GFRC. SEM was applied to observe the underlying microstructural changes of CSA/GFRC under different curing regimes. It was found out that there was a gradual degradation of both ultimate tensile strength and ultimate strain of CSA/GFRC with elevated curing temperature and curing age, but glass fibre still shows considerable ability to carry stress alone by bridging cracks. Microstructural studies showed that, at accelerated temperatures of 50°C and 70°C, the space between fibres remained empty in general only with some hydration products adhering to the fibre surface occasionally. At a higher accelerated curing temperature of 80°C, densification of the interfilamentary spaces by larger and clustered hydration products can be observed at longer curing ages, causing the fibres to lose parts of the flexibility. Therefore, it can be concluded that densification of interfilamentary spaces may have a greater role to play in the strength degradation of CSA/GFRC than mechanisms associated with fibre weakening caused by chemical corrosion.

show abstract

Section: Introductionmentioning

confidence: 99%

Durability of GFRC Modified by Calcium Sulfoaluminate Cement under Elevated Curing Temperatures

Song

Dou

2019

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

show abstract

“…While the industrial benefits of these later methods are undeniable [14], the availability of raw materials for the necessary impurities can be a concern. At this point, development of C 2 S-rich cements as an alternative to OPC is an active field of research [15][16][17][18][19][20]. Contradictory to the vast research interests regarding C 2 S, potential applications of CS and C 3 S 2 in cementbased materials have not yet been thoroughly explored.…”

Section: Introductionmentioning

confidence: 97%

Carbonation behavior of hydraulic and non-hydraulic calcium silicates: potential of utilizing low-lime calcium silicates in cement-based materials

2016

View full text Add to dashboard Cite

This paper presents a study on the carbonation behaviors of hydraulic and nonhydraulic calcium silicate phases, including tricalcium silicate (3CaOÁSiO 2 or C 3 S), c-dicalcium silicate (c-2CaOÁSiO 2 or c-C 2 S), b-dicalcium silicate (b2CaOÁSiO 2 or b-C 2 S), rankinite (3CaOÁ2SiO 2 or C 3 S 2 ), and wollastonite (CaOÁSiO 2 or CS). These calcium silicate phases were subjected to carbonation reaction at different CO 2 concentration and temperatures. Thermogravimetric analysis (TGA) tests were performed to quantify the amounts of carbonates formed during the carbonation reactions, which were eventually used to monitor the degree of reactions of the calcium silicate phases. Both hydraulic and non-hydraulic calcium silicates demonstrated higher reaction rate in case of carbonation reaction than that of the hydration reaction. Under specific carbonation scenario, non-hydraulic low-lime calcium silicates such as c-C 2 S, C 3 S 2 and CS were found to achieve a reaction rate close to that of C 3 S. Fourier transformed infrared (FTIR) spectroscopy and scanning electron microscope (SEM) tests were performed to characterize the carbonation reaction products of the calcium silicate phases. The FTIR spectra during the early stage of carbonation reaction showed formation of calcium silicate hydrate (C-S-H) from C 3 S, c-C 2 S, b-C 2 S, and C 3 S 2 phases with a similar degree of polymerization as that of the C-S-H that forms during the hydration reaction of C 3 S. However, upon further exposure to CO 2 , these C-S-H phases decompose and eventually converted to calcium-modified (Ca-modified) silica gel phase with higher degree of silicate polymerization. Contradictorily, CS phase started forming Ca-modified silica gel phase even at the early stage of carbonation reaction. This paper also revealed the stoichiometry of the Ca-modified silica gel that formed during the carbonation reaction of the calcium silicate phases using the SEM/energy dispersive spectroscopy (EDS) and TGA results.

show abstract

“…A general pore size classification is given by the International Union of Pure and Applied Chemistry (IUPAC), where pores are divided into micropores (d < 1.25 nm), mesopores (1.25 nm ≤ d ≤ 25 nm), macropores (25 nm ≤ d ≤ 5000 nm), and entrained air voids, entrapped air voids, and pre-existing microcracks (5000 nm ≤ d ≤ 50000 nm). It is evident that there is a great difference between the two cementitious mortars R3 OPC and R3 CSA, which both show a unimodal pore distribution with average diameters of around 100 and 35 nm, The elevated compressive strength gained by the R3 CSA mortar after just seven days of curing is related to the formation of ettringite [21,[53][54][55], which is the principle hydration product in calcium sulfoaluminate matrices. The morphology of ettringite crystals is influenced by the availability of space and the concentration of Ca 2+ and SO 4 2− ions [28,56].…”

Section: Microstructural Analyses Of Mortarsmentioning

confidence: 99%

“…The elevated compressive strength gained by the R3 CSA mortar after just seven days of curing is related to the formation of ettringite [21,[53][54][55], which is the principle hydration product in calcium sulfoaluminate matrices. The morphology of ettringite crystals is influenced by the availability of space and the concentration of Ca 2+ and SO4 2− ions [28,56].…”

Section: Mechanical Properties Of Mortarsmentioning

confidence: 99%

Calcium Sulfoaluminate, Geopolymeric, and Cementitious Mortars for Structural Applications

et al. 2017

View full text Add to dashboard Cite

This paper deals with the study of calcium sulfoaluminate (CSA) and geopolymeric (GEO) binders as alternatives to ordinary Portland cement (OPC) for the production of more environmentally-friendly construction materials. For this reason, three types of mortar with the same mechanical strength class (R3 ≥ 25 MPa, according to EN 1504-3) were tested and compared; they were based on CSA cement, an alkaline activated coal fly ash, and OPC. Firstly, binder pastes were prepared and their hydration was studied by means of X-ray diffraction (XRD) and differential thermal-thermogravimetric (DT-TG) analyses. Afterwards, mortars were compared in terms of workability, dynamic modulus of elasticity, adhesion to red clay bricks, free and restrained drying shrinkage, water vapor permeability, capillary water absorption, and resistance to sulfate attack. DT-TG and XRD analyses evidenced the main reactive phases of the investigated binders involved in the hydration reactions. Moreover, the sulfoaluminate mortar showed the smallest free shrinkage and the highest restrained shrinkage, mainly due to its high dynamic modulus of elasticity. The pore size distribution of geopolymeric mortar was responsible for the lowest capillary water absorption at short times and for the highest permeability to water vapor and the greatest resistance to sulfate attack.

show abstract

Hydration of ordinary Portland cement and calcium sulfoaluminate cement blends

Cited by 203 publications

References 27 publications

Durability of GFRC Modified by Calcium Sulfoaluminate Cement under Elevated Curing Temperatures

Durability of GFRC Modified by Calcium Sulfoaluminate Cement under Elevated Curing Temperatures

Carbonation behavior of hydraulic and non-hydraulic calcium silicates: potential of utilizing low-lime calcium silicates in cement-based materials

Calcium Sulfoaluminate, Geopolymeric, and Cementitious Mortars for Structural Applications

Contact Info

Product

Resources

About