Influence of dispersing agents on the rheology and early heat of hydration of blended cements with high loading of calcined marl

2015 ◽  
Vol 60 ◽  
pp. 123-134 ◽  
Author(s):  
S. Ng ◽  
H. Justnes
Keyword(s):  
Heat Of Hydration ◽  
High Loading ◽  
Blended Cements ◽  
Dispersing Agents

SETTING TIME AND HEAT OF HYDRATION OF WASTEPAPER SLUDGE ASH-GROUND GRANULATED BLASTFURNACE SLAG BLENDED CEMENTS

2005 ◽  
pp. 825-834 ◽  
Author(s):  
Arnon Chaipanich ◽  
J Bai ◽  
M O'Farrell ◽  
J M Kinuthia ◽  
B B Sabir ◽  
...  
Keyword(s):  
Setting Time ◽  
Heat Of Hydration ◽  
Blended Cements ◽  
Blastfurnace Slag ◽  
Sludge Ash

scholarly journals RELATIONSHIP BETWEEN HEAT OF HYDRATION AND COMPRESSIVE STRENGTH IN BLENDED CEMENTS

2015 ◽  
Vol 69 (1) ◽  
pp. 191-198
Author(s):  
Yuya YODA ◽  
Yutaka AIKAWA ◽  
Daiki ATARASHI ◽  
Etsuo SAKAI
Keyword(s):  
Compressive Strength ◽  
Heat Of Hydration ◽  
Blended Cements

scholarly journals Characteristics of Blended Cements Produced from Selected Hardwood Ashes

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Akeem A Raheem ◽  
Blessing O Orogbade
Keyword(s):  
Chemical Composition ◽  
Wood Ash ◽  
Heat Of Hydration ◽  
Cement Clinker ◽  
Potassium Oxide ◽  
Cassia Siamea ◽  
Suitable Material ◽  
Blended Cements ◽  
Setting Times ◽  
Portland Cement Clinker

In an attempt to find an alternative binding material for construction industry, this study considered the use of wood ash from three different hardwoods namely: Tectonagrandis, Cassia siamea and Vitellariaparadoxa as a pozzolan in cement production. The study investigates the chemical composition (silica (SiO2), aluminum oxide (Al2O3), ferric oxide (Fe2O3), calcium oxide (CaO), magnesium oxide (MgO), sulphur trioxide (SO3), sodium oxide (Na2O) and potassium Oxide (K2O)) of the ashes and the clinker. The production of blended cements were carried out in the factory by replacing 5- 50% by weight of Ordinary Portland Cement Clinker with the ashes during the manufacturing process. The cement without wood ash serves as the control. The physical characteristic (fineness, initial and final setting times, heat of hydration and residue on 45µm sieve), and the chemical composition of the blended cements were also investigated. The results showed that all the wood ashes (Tectonagrandis ash (TGA), Cassia siamea ash (CSA) and Vitellariaparadoxa ash (VPA)) were suitable material for use as pozzolan since they satisfied the requirement for such a material by having a combined SiO2, Fe2O3 and Al2O3 of more than 70%. The TGA, CSA and VPA blended cements satisfied standard requirements for up to 20% replacement level. It was concluded that all the wood ashes were suitable for use in the production of blended cements.

scholarly journals Hydration behaviour of limestone-calcined clay and limestone-slag blends in ternary cement

2021 ◽  
Vol 6 ◽  
pp. 17-24
Author(s):  
Anuj Parashar ◽  
Shashank Bishnoi
Keyword(s):  
Bound Water ◽  
Heat Of Hydration ◽  
Cement Clinker ◽  
Strength Development ◽  
Gravimetric Analysis ◽  
Calcined Clay ◽  
X Ray ◽  
Blended Cements ◽  
Degree Of Hydration ◽  
Hydration Behaviour

The effect of kaolinitic calcined clay and slag on the hydration of limestone-containing ternary blended cements was investigated. The effect of alumina from different sources of SCMs was considered to activate the formation of carboaluminates. Ternary blends with 50% ordinary portland cement clinker, 45% blends of limestone calcined clay (LC2) in 1:2 blend and slag limestone blend (SLS) in 2:1 mix proportion with 5% of gypsum were studied. The hydration behaviour was analysed based on cement mortar compressive strength, heat of hydration using an isothermal calorimeter and bound water measured using thermal gravimetric analysis (TGA). In addition, the degree of hydration of clinker phases and the composition of calcium - alumino - silicate - hydrate (C-A-S-H) gels forming in two different systems were compared on 90 days hydrated samples analysed using X-Ray diffractometry (XRD) and scanning electron microscopy - energy dispersive X-ray spectroscopy (SEM-EDX) respectively. The results show a rapid early strength development in limestone calcined clay cement blend (LC3) but a lower clinker hydration in comparison with slag limestone cement blend (SLSC) at later ages. In both the cement blends the formation of hemicarboaluminate (Hc) and monocarboaluminate (Mc) was confirmed at 90 days, but the conversion of Hc to Mc was higher in SLSC. Results further confirmed a lower degree of hydration and higher alumina incorporation in the C-A-S-H gel in the LC3 comparison to SLSC. The presence of calcium hydroxide was also confirmed in the SLSC blend due to the hydraulic nature of slag that supported the later age conversion of Hc to Mc as not seen in LC3.

scholarly journals The effects of seawater and nanosilica on the performance of blended cements and composites

2020 ◽  
Vol 10 (12) ◽  
pp. 5009-5026 ◽  
Author(s):  
Pawel Sikora ◽  
Didier Lootens ◽  
Maxime Liard ◽  
Dietmar Stephan
Keyword(s):  
Transport Properties ◽  
Reaction Rate ◽  
Mechanical Performance ◽  
Setting Time ◽  
Blended Cement ◽  
Heat Of Hydration ◽  
Strength Development ◽  
Cement Pastes ◽  
Blended Cements ◽  
Setting Times

AbstractThis study investigates the effects of seawater and nanosilica (3% by weight of cement), on the fresh and hardened properties of cement pastes and mortars produced with two types of low heat cements: Portland pozzolana cement (CEM II) and blast furnace cement (CEM III). The heat of hydration, initial and final setting times, rheological properties, strength development, sorptivity and water accessible porosity of the cement pastes and mortars were determined. The data reveal that cement type has a significant effect on the reaction rate of cement with seawater and nanosilica (NS). Specimens produced with slag-blended cement exhibited a higher cement reaction rate and the composite produced exhibited better mechanical performance, as a result of the additional reaction of alumina rich phases in slag, with seawater. Replacement of freshwater with seawater contributes mostly to a significant improvement of early strength. However, in the case of slag-blended cement, 28 day strength also improved. The incorporation of NS results in additional acceleration of hydration processes, as well as to a decrease in cement setting time. In contrast, the addition of NS results in a noticeable increment in the yield-stress of pastes, with this effect being pronounced when NS is mixed along with seawater. Moreover, the use of seawater and NS has a beneficial effect on microstructure refinement, thus improving the transport properties of cement mortars. Overall, the study has showed that both seawater and NS can be successfully used to accelerate the hydration process of low heat blended cements and to improve the mechanical and transport properties of cement-based composites.

scholarly journals Study of the Properties of Blended Cements Containing Various Types of Slag Cements and Limestone Powder

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6072
Author(s):  
Małgorzata Gołaszewska ◽  
Zbigniew Giergiczny
Keyword(s):  
Particle Size ◽  
Compressive Strength ◽  
Particle Size Distribution ◽  
Rheological Properties ◽  
Size Distribution ◽  
Heat Of Hydration ◽  
Limestone Powder ◽  
Engineering Practice ◽  
Negative Effects ◽  
Blended Cements

It is currently vital to use more environmentally friendly cementitious composites, such as blended slag-limestone cements. However, many properties of slag-limestone cements are not yet fully research, especially in regards to the effect of limestone properties on properties of mortars and concrete. In the research, three types of slag cements were mixed with two types of limestone to obtain multi-component slag-limestone cements. Tests of rheological properties, heat of hydration, and compressive strength were conducted to ascertain the effect of limestone on the cement properties and to check the viability of this type of cement for engineering practice. It was found that the addition of up to 10% of limestone to slag cements did not have negative effects on tested properties; however, the exact influence of limestone was dependent on limestone particle size distribution. Increasing the amount of limestone in limestone-slag cements to 15% significantly decreased the compressive strength of the mortars and decreased hydration heat but had no significant effect on rheological properties.

scholarly journals Chemical and Physical Characteristics of Blended Cements Produced from Softwood Ash

2018 ◽  
Vol 1 (March 2018) ◽  
pp. 1-7
Author(s):  
B.O Orogbade ◽  
A.A Raheem
Keyword(s):  
Chemical Composition ◽  
Wood Ash ◽  
Heat Of Hydration ◽  
Cement Clinker ◽  
Potassium Oxide ◽  
Agricultural Residue ◽  
Suitable Material ◽  
Blended Cements ◽  
Setting Times ◽  
Portland Cement Clinker

In an attempt to convert agricultural residue to alternative binding material for use in construction industry, this research considered the use of wood ash from Anacardium- occidentale (kaju) wood which is softwood as a pozzolan in cement production. In this study, the chemical composition (silica (SiO.), aluminum oxide (AI,O,), ferric oxide (Fe,O,), calcium oxide (CaQ), magnesium oxide (MgO), sulphur trioxide (SO,), sodium oxide (Na,O) and potassium Oxide (K,O)) of the ashes and the clinker was investigated. The production of blended cements were carried out in the factory by replacing 5- 50% by weight of Ordinary Portland Cement Clinker with the ashes during the manufacturing process. The cement without wood ash serves as the control. The physical characteristic (fineness, initial and final setting times, heat of hydration and residue on 45um sieve), and the chemical composition of the blended cements were also investigated. The results showed that Anacardiumoccidentale ash (AOA) was a suitable material for use as pozzolan since it satisfied the requirement for such a material by having a combined SiO, Fe,O,and Al,O,of more than 70% according to ASTM C 618. The AOA blended cements satisfied standard requirements for up to 20% replacement level. It was concluded that the wood ash was suitable for use in the production of blended cements.

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