Use of incinerator ash as a replacement for cement and sand in cement mortars

This work reports on the incorporation of Flint and Kaolin rocks powders in the cement mortar in an attempt to improve its mechanical properties and produce an eco-friendly mortar. Flint and Kaolin powders are prepared by dry mechanical milling. The two powders are added separately to the mortars substituting cement partially. The two powders are found to improve the mechanical properties of the mortars. Hardness and compressive strength are found to increase with the increase of powders constituents in the cement mortars. In addition, the two powders affect water absorption and thermal conductivity of the mortar specimens which are desirable for construction applications. Kaolin is found to have a greater effect on the mechanical properties, water absorption, and thermal conductivity of the mortars than Flint. This behavior is discussed and analyzed based on the compositional and structural properties of the rocks powders.

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The Influence of the Ash Addition from Thermal Power Plant on the Mechanical, Thermal and Dielectric Characteristics of Mortars

Revista de Chimie ◽

10.37358/rc.18.8.6469 ◽

2018 ◽

Vol 69 (8) ◽

pp. 2040-2044

Author(s):

Georgeta Velciu ◽

Virgil Marinescu ◽

Adriana Moanta ◽

Ladislau Radermacher ◽

Adriana Mariana Bors

Keyword(s):

Thermal Conductivity ◽

Fly Ash ◽

Power Plant ◽

Cement Mortar ◽

Thermal Power ◽

Total Content ◽

Ash Content ◽

Dielectric Losses ◽

Dielectric Characteristics ◽

Cement Mortars

The influence of fly ash adittion (90 % fraction [ 100 mm) on the cement mortar characteristics was studied. The XRD, XRF, SEM and FTIR determinations indicated that fly ash used has a hollow microstructure of microsphere and cenosphere whose total content in SiO2, Al2O3 and Fe2O3 is 88.63 % and that of CaO and MgO of 8.55 %. The mechanical, thermal and dielectric determinations made on mortar samples with content of fly ash in the 0-40 % range have highlighted fact that the mechanical strength of cement mortars is maximal at 20 %, the increase in fly ash content leads to a decrease in relative density and thermal conductivity as well as and to increased dielectric losses tgd.

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Properties of Calcium Sulfoaluminate Cement Mortar Modified by Hydroxyethyl Methyl Celluloses with Different Degrees of Substitution

Molecules ◽

10.3390/molecules26082136 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2136

Author(s):

Shaokang Zhang ◽

Ru Wang ◽

Linglin Xu ◽

Andreas Hecker ◽

Horst-Michael Ludwig ◽

...

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Bond Strength ◽

Cement Mortar ◽

Retention Rate ◽

Methyl Cellulose ◽

Tensile Bond Strength ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate ◽

Cement Mortars

This paper studies the influence of hydroxyethyl methyl cellulose (HEMC) on the properties of calcium sulfoaluminate (CSA) cement mortar. In order to explore the applicability of different HEMCs in CSA cement mortars, HEMCs with higher and lower molar substitution (MS)/degree of substitution (DS) and polyacrylamide (PAAm) modification were used. At the same time, two kinds of CSA cements with different contents of ye’elimite were selected. Properties of cement mortar in fresh and hardened states were investigated, including the fluidity, consistency and water-retention rate of fresh mortar and the compressive strength, flexural strength, tensile bond strength and dry shrinkage rate of hardened mortar. The porosity and pore size distribution were also analyzed by mercury intrusion porosimetry (MIP). Results show that HEMCs improve the fresh state properties and tensile bond strength of both types of CSA cement mortars. However, the compressive strength of CSA cement mortars is greatly decreased by the addition of HEMCs, and the flexural strength is decreased slightly. The MIP measurement shows that HEMCs increase the amount of micron-level pores and the porosity. The HEMCs with different MS/DS have different effects on the improvement of tensile bond strength in different CSA cement mortars. PAAm modification can improve the tensile bond strength of HEMC-modified CSA cement mortar.

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Evaluation of sulfate resistance of cement mortars containing black rice husk ash

Journal of Environmental Management ◽

10.1016/j.jenvman.2008.09.001 ◽

2009 ◽

Vol 90 (3) ◽

pp. 1435-1441 ◽

Cited By ~ 46

Author(s):

B. Chatveera ◽

P. Lertwattanaruk

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Black Rice ◽

Sulfate Resistance ◽

Cement Mortars

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Effect of C-S-H Nucleating Agent on Cement Hydration

Applied Sciences ◽

10.3390/app11146638 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6638

Author(s):

Wenhao Zhao ◽

Xuping Ji ◽

Yaqing Jiang ◽

Tinghong Pan

Keyword(s):

Fractal Dimension ◽

Cement Hydration ◽

Nucleating Agent ◽

Crystal Nucleation ◽

Enhancement Effect ◽

Hydration Products ◽

Hydration Degree ◽

Hydration Kinetics ◽

Cement Mortars ◽

Early Strength

This work aims to study the effect of a nucleating agent on cement hydration. Firstly, the C-S-H crystal nucleation early strength agent (CNA) is prepared. Then, the effects of CNA on cement hydration mechanism, early strength enhancement effect, C-S-H content, 28-days hydration degree and 28-days fractal dimension of hydration products are studied by hydration kinetics calculation, resistivity test, BET specific surface area test and quantitative analysis of backscattered electron (BSE) images, respectively. The results show that CNA significantly improves the hydration degree of cement mixture, which is better than triethanolamine (TEA). CNA shortens the beginning time of the induction period by 49.3 min and the end time of the cement hydration acceleration period by 105.1 min than the blank sample. CNA increases the fractal dimension of hydration products, while TEA decreases the fractal dimension. CNA significantly improves the early strength of cement mortars; the 1-day and 3-days strength of cement mortars with CNA are more than the 3-days and 7-days strength of the blank sample. These results will provide a reference for the practical application of the C-S-H nucleating agent.

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