Jiaxin Liu , Chentao Zhu , Xiong Yu (Bill) , Chanjuan Han
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引用次数: 0
Abstract
Bentonite, widely employed in geotechnical projects, faces a pressing challenge in addressing desiccation cracking. Leveraging its high latent heat, microencapsulated phase change material (microPCM) holds promise in ameliorating this issue. This study pioneers the application of microPCM as an additive to enhance bentonite's resistance to cracking. Employing an automated measurement platform, a series of desiccation cracking tests were conducted on bentonite blends with varying microPCM contents. Techniques including mercury intrusion porosimetry, scanning electron microscopy, digital image processing, infrared thermography, and particle image velocimetry, were employed to elucidate these mechanisms. Quantitative metrics were defined and meticulously analyzed across samples with different microPCM ratios. Additionally, qualitative and quantitative assessments of pore structure features were conducted. Key findings demonstrate that the incorporation of microPCM can delay evaporation by up to 33 % (at a microPCM mass fraction of 15 %) while intensifying volumetric contraction. This delay effectively postpones crack initiation and doubles crack propagation duration. However, microPCM agglomeration tendencies leading to formation of additional cavities may act as initial defects in the bentonite. This study not only illuminates the potential of microPCM as an effective additive in enhancing bentonite's resistance to desiccation cracking but also identifies associated challenges, thus paving the way for further innovative research.
期刊介绍:
Applied Clay Science aims to be an international journal attracting high quality scientific papers on clays and clay minerals, including research papers, reviews, and technical notes. The journal covers typical subjects of Fundamental and Applied Clay Science such as:
• Synthesis and purification
• Structural, crystallographic and mineralogical properties of clays and clay minerals
• Thermal properties of clays and clay minerals
• Physico-chemical properties including i) surface and interface properties; ii) thermodynamic properties; iii) mechanical properties
• Interaction with water, with polar and apolar molecules
• Colloidal properties and rheology
• Adsorption, Intercalation, Ionic exchange
• Genesis and deposits of clay minerals
• Geology and geochemistry of clays
• Modification of clays and clay minerals properties by thermal and physical treatments
• Modification by chemical treatments with organic and inorganic molecules(organoclays, pillared clays)
• Modification by biological microorganisms. etc...