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Preparation and Performance Investigation of Optimized Cement-Based Sealing Materials Based on the Response Surface
Junxiang Zhang1,2,3, Bo Li2,4, Bo Wang2
1School of Energy & Environment Engineering, Zhongyuan University of Technology, Zhengzhou, Henan 451191, China.
ACS Omega
|August 1, 2022
Summary
Researchers developed a new cement-based sealing material using Portland cement and additives. Optimization studies identified key factors influencing fluidity, setting time, and expansion, leading to improved material performance and microstructure.
Area of Science:
- Materials Science
- Civil Engineering
- Geotechnical Engineering
Background:
- Traditional cement-based materials face limitations in specific sealing applications.
- The development of advanced sealing materials is crucial for infrastructure and environmental protection.
Purpose of the Study:
- To develop and optimize a novel cement-based sealing material using Portland cement and various gel components.
- To investigate the influence of key additives on the material's fluidity, setting time, and expansion rate.
- To establish regression models and response surfaces for predicting and optimizing material performance.
Main Methods:
- Preparation of cement-based sealing material with Portland cement and additives (accelerant, alkali activator, suspension agent, expansion agent, reinforcing agent).
- Orthogonal experimental design to systematically study the effects of component ratios on material properties.
- Multiple linear regression analysis to establish predictive models and visualize factor influences via response surfaces.
Main Results:
- Identified critical influencing factors: water-cement ratio and reinforcing agent for fluidity; accelerant and water-cement ratio for setting time; expansion agent and accelerant for expansion rate.
- Determined optimal composition: water-cement ratio of 1.1, 50% accelerant, 0.1% expansion agent, and 3% reinforcing agent.
- Achieved optimal performance: fluidity 360-380 mm, initial (final) setting time 60 (80)-80 (100) min, expansion rate 2-12%.
Conclusions:
- The optimized cement-based sealing material exhibits significantly improved properties compared to conventional formulations.
- Microstructural analysis reveals a transformation from layered Ca(OH)2 to needle-like AFt crystals and C-S-H gels, indicating enhanced structural integrity.
- The developed material holds promise for specialized sealing applications requiring controlled expansion and durability.
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