Strength effect and mechanism analysis of MICP-solidified coal ash

WANG Ziwen; WEI Ran; WU Shuaifeng; TIAN Jixue; LIANG Shujun

doi:10.11779/CJGE2023S10052

Volume 45 Issue S1

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Chinese Journal of Geotechnical Engineering > 2023 > 45(S1): 88-91. > DOI: 10.11779/CJGE2023S10052

WANG Ziwen, WEI Ran, WU Shuaifeng, TIAN Jixue, LIANG Shujun. Strength effect and mechanism analysis of MICP-solidified coal ash[J]. Chinese Journal of Geotechnical Engineering, 2023, 45(S1): 88-91. DOI: 10.11779/CJGE2023S10052

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Strength effect and mechanism analysis of MICP-solidified coal ash

WANG Ziwen^{1, 2,},
WEI Ran³,
WU Shuaifeng^{1, 2},
TIAN Jixue^{1, 2},
LIANG Shujun⁴

1.
State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
2.
MWR Key Lab of Key Lab of Construction and Safety of Water Engineering, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
3.
Beihang University, Beijing 102206, China
4.
Shijingshan Thermal Power Plant of Beijing Jingneng Power Co., Ltd., Beijing 100000, China

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Received Date: July 04, 2023
Available Online: November 23, 2023

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Abstract

Abstract

The coal ash has the characteristics of fine particles, small specific gravity and large pore ratio. In order to achieve effective utilization of the coal ash and dust pollution control, the microbial induced carbonate precipitation (MICP) method is used, considering natural evaporation and wet cylinder maintenance conditions, to study the mechanism of microbial response, strengthening characteristics and influencing factors. The results show that: (1) The calcite is the calcium carbonate produced by microorganisms in the coal ash, and the content increases from 7% to 15.3%. (2) Under the MICP wet cylinder curing conditions, the maximum unconfined compressive strength increases by 6.55 times, reaching 97.63 kPa. (3) The solidification strength first increases and then decreases with the increase of the nutrient concentration, and the optimal nutrient concentrations under moisturizing cylinder and natural evaporation conditions are 0.5 and 1.0 mol/L, respectively. (4) The microbial-derived calcium carbonate can reduce the water loss in ash samples and has a significant water retention effect, indicating good prospects for dust suppression applications.
- MICP,
- coal ash,
- strength effect,
- mechanism analysis

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