摘要
为了有效增强风积砂土体的稳定性并确保基础设施的安全使用,研究综合评估了糖钙络合物、玻璃纤维(Glass Fiber, GF)以及微生物诱导碳酸钙沉淀(Microbial Induced Calcium Carbonate Precipitation, MICP)技术的优势,并提出了一种新型的、环境友好的风积砂固化改良技术,即糖钙络合物-GF-MICP联合加固体系。通过一系列室内固化试验,结合宏观力学试验、压汞试验和扫描电镜试验表征,系统地探讨了该加固体系的作用机制。试验结果显示:(1)当糖钙络合物与GF-MICP技术结合使用时,风积砂试样的强度随着糖钙络合物的添加而显著增加,并在添加质量分数为4%时达到最大值2 515 kPa,与未添加糖钙络合物的试样相比,强度提升了867%。(2)糖钙络合物在参与固化反应后,固化试样的平均孔径从0.013 mm降低至0.003 6 mm,孔隙率显著下降,提高了整体的密实性和抗渗性能,且渗透系数也随之降低。(3)在糖钙络合物-GF-MICP联合加固的试样中,碳酸钙的质量分数从6%增加到了19%。此外,玻璃纤维为碳酸钙晶体提供了成核空间,并通过颗粒间的拉结作用进一步增强了试样的整体稳定性。(4)通过X射线衍射试验和扫描电镜试验分析,发现糖钙络合物-GF-MICP加固后的试样中产生了大量的碳酸钙胶结物质。同时,糖钙络合物分解产生的单糖分子、蔗糖分子与水分子形成的分子间力有效地黏结了砂颗粒,使得经过加固体系固化的试样展现出强大的联结性。
To effectively enhance the stability of wind-deposited sand and ensure the safe use of infrastructure,this study comprehensively evaluates the benefits of sugar-calcium complexes,Glass Fibers(GF),and Microbial-Induced Calcium Carbonate Precipitation(MICP)technology.It proposes a novel environmentally friendly consolidation and improvement method for windlogged sand:the sugar-calcium complexes GF MICP joint reinforcement system.A series of indoor curing tests,along with macro-mechanical tests,mercury intrusion tests,and Scanning Electron Microscope(SEM)analyses,were conducted to systematically explore the mechanism of action of this reinforcement system.The test results indicate that:(1)The addition of the sugar-calcium complex led to an increase in the strength of the cured specimens,reaching a peak value of 2515 kPa at a dosage of 4%.This represents an 867%increase in strength compared to specimens without the sugar-calcium complex.(2)The average pore size of the cured specimens decreased from 0.013 mm with traditional microbial reinforcement to 0.0036 mm with the inclusion of the calcium saccharide complex in the curing reaction.This resulted in a significant reduction in porosity,enhancing overall densification and seepage resistance,and consequently lowering the permeability coefficient.(3)The calcium carbonate content in the specimens reinforced with the combined sugar-calcium complex,GF,and MICP increased from 6%to 19%.Additionally,the glass fibers provided nucleation sites for the calcium carbonate crystals,enhancing the overall stability of the specimens through inter-particle tensile bonding.(4)Analysis of the X-ray Diffraction and SEM tests revealed that the sugar-calcium complex,GF,and MICP reinforced particles formed a significant amount of calcium carbonate cement between them.Simultaneously,the intermolecular forces generated by the monosaccharide molecules,sucrose molecules,and water produced from the decomposition of the sugar-calcium complex effectively bonded the sand particles.As a result,the specimens cured with this reinforcement system exhibited strong bonding properties.
作者
刘小军
朱芮
孙跃
王东亚
LIU Xiaojun;ZHU Rui;SUN Yue;WANG Dongya(School of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;Key Laboratory of Geotechnical and Underground Space Engineering of Shaanxi Province,Xi'an 710055,China)
出处
《安全与环境学报》
北大核心
2025年第6期2387-2397,共11页
Journal of Safety and Environment
基金
陕西省自然科学基础研究计划项目(2020JM-483)。
关键词
环境工程学
微生物诱导碳酸钙沉淀
风积砂
力学特性
机理分析
environmental engineering
microbial-induced calcium carbonate precipitation
windlogged sand
mechanical properties
microscopic analysis
