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An experimental study on the curing of desert sand using bio-cement
1School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China. 22104053010@stu.xust.edu.cn.
Bioresources and Bioprocessing
|July 20, 2024
Summary
This study enhances desert sand using bio-cement and fly ash, improving its shear strength and permeability. Tap water is suitable for bio-cement preparation, offering a sustainable construction material.
Area of Science:
- Civil Engineering
- Biotechnology
- Environmental Science
Background:
- Desert sand utilization is limited by poor mechanical properties.
- Bio-cementation offers a sustainable approach to soil improvement.
- Integrating fly ash may enhance bio-cement performance.
Purpose of the Study:
- Determine optimal bio-cement ratios for desert sand.
- Analyze shear strength and permeability of bio-cemented sand with fly ash.
- Assess tap water's applicability in bio-cementation.
Main Methods:
- Conducted shear strength and permeability tests on modified desert sand.
- Investigated microstructural properties using microscopy.
- Analyzed urease activity and calcium carbonate precipitation.
Main Results:
- Tap water-based urease solutions showed enhanced temperature resistance.
- Optimal urea concentration for urease activity was 1.0-1.5 mol/L.
- Increased fly ash content improved shear strength by 37.9% and reduced permeability by 8.9-68.5%.
Conclusions:
- Bio-cementation with fly ash effectively improves desert sand's mechanical properties.
- Fly ash acts as nucleation sites, enhancing bio-cement performance.
- Calcite and aragonite were the stable calcium carbonate crystal types formed.
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