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Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Waste glass powder and metakaolin were used to prepare geopolymer mortar. The effects of alkali activator with different sodium silicate modulus and liquid-solid ratios on the fluidity and mechanical properties of the waste glass powder-metakaolin geopolymer mortar were investigated, and the crystal structure, thermochemistry, pore structure, and micromorphology of the geopolymer mortar were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric-differential scanning thermal (TG-DSC), mercury in piezoelectricity (MIP), and scanning electron microscopy (SEM). The results show that the sodium silicate modulus and liquid-solid ratio have more obvious effects on the fluidity and mechanical properties of the geopolymer mortar. With the increase of sodium silicate modulus, the fluidity and strength of geopolymer mortar increase first and then decrease. When the sodium silicate modulus is 1.25, the alkali activator has the best excitation effect on the material, which increases the degree of reaction of the geopolymer, generates more hydration products, optimizes the pore structure of the matrix, and the compressive strength of 28 d reaches 43.0 MPa. The increase of liquid-solid ratio improves the fluidity of the geopolymer mortar, but decreases the compressive strength and has a negative effect on the pore structure. Moreover, the XRD, FTIR and TG-DSC results show that the waste glass in the geopolymer participates in the hydration reaction, provides Ca2+, and promotes the generation of C-S-H and C-A-S-H gels. [ABSTRACT FROM AUTHOR]

In order to achieve the resource utilization of beach silty soil and industrial wastes, and quantitatively optimize the critical factors of geopolymer cured silty soil, the mix ratio of alkali-activated slag-fly ash based geopolymer cured silty soil was optimized based on the Box-Behnken response surface method. The slag content, alkali activator modulus and alkali activator content were selected as the main factors to be investigated, and the curing mechanism was analyzed by combining the macroscopic properties and microscopic morphology. The results show that: the optimum mix ratio of cured soil is slag content 86.5% (mass fraction), alkali activator modulus 0.84, alkali activator content 7.3% (mass fraction), the unconfined compressive strength of cured soil at 7 and 28 d under the optimum mix ratio is 5 823 and 7 027 kPa, respectively. The prediction value has a small error with the actual value, and the established model is accurate and reliable in fitting the actual data. The hydration products of cured soil are mainly amorphous gel hydrated calcium silica-aluminate (C-(A)-S-H) and silica-aluminate polymer (N-A-S-H), which enhance the densification and skeletal structure of soil body, thus improving the strength of cured soil. This study provides a theoretical basis and experimental foundation for alkali-activated geopolymer cured silty soil. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With excellent mechanical properties and durability, alkali-activated cementitious material prepared by industrial solid waste is a kind of green inorganic cementitious material. Fly ash is essentially different from other solid waste because of its unique spherical microstmcture, therefore, the reaction mechanism of fly ash in alkali-activated cementitious material needs to be studied. In this paper, slag and fly ash were used as raw materials to prepare cementitious materials by alkali activator. The compressive strength of the material was tested, and the hydration mechanism of alkali-activated slag/fly ash system was explored by XRD, FTIR, and SEM. The detailed effect of fly ash on alkali-activated slag/fly ash system and related mechanisms were investigated. The results show that, when 3% (mass fraction) NaOH is added as alkali activator, and the water-solid ratio is 0.4, with the decrease of fly ash content, the compressive strength first increases and then decreases. When m(slag) : m(fly ash) is 4:1, 28 d compressive strength reaches the peak value of 37.1MPa. Embedded microstmcture of fly ash particles has different reaction degrees and sizes at different ages, which has a negative effect on the mechanical properties of the material. However, the activation degree of fly ash gradually increases with the extension of age, which has a continuous contribution to the later strength development. The hydration products of alkali-activated slag/fly ash system contain Friedel's salt, tobennorite, ettringite, C-S-H/C-A-S-H gel, and residual alpha quartz of fly ash. With the increase of fly ash content, the amount of tobennorite decreases, ettringite transforms into Friedel's salt, the production of ettringite decreases, and the production of Friedel's salt increases. [ABSTRACT FROM AUTHOR]