混凝土泛碱机理分析

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中图分类号：TV431 文献标志码：A 文章编号：1005-8249（2025）06-0029-07

Abstract：Toinvestigatetheeflorescencemechanismofconcreteinwaterconservancyprojects inNorthwestChia，acelerated tests wereconducted using awet-drycycling method.The studycomprehensively characterized the eflorescence phenomenon through multiple micro-analytical techniques，including X-raydifraction（XRD），scanning electron microscopy（SEM）， thermogravimetry- derivative thermogravimetry （TG- DTG），and proton nuclear magnetic resonance （ 1HNMR ）. Key findings are as follows： The main efflorescence products were identified as CaCO3 ， Na2SO4 ， SiO2 ， K3Na （ SO4 ），and minor salts; Afteraccelerated efforescence treatment，concrete specimens showed significantly greater massloss inthe range of 200-500∘C （204 and higher Ca （OH）2 content compared to standard -cured specimens，with notable enrichment at depths of 0～2 and 8～ （204号 10 mm；Efflorescence coarsened the pore structure：the proportion of mesopores decreased by 77.99% ，while those of macropores and microcracks increased by 19.75% and 10.27% ，respectively，with little change in micropore content.These results demonstratethateflorescenceincreasesconcreteporosityanddegradesthepore-sizedisribution，therebyadverselyaffecting thecompactnesanddurabilityofthematerial.Theresearchresultsprovideatheoreticalbasisfortheprotectionof water conservancy projects.

Key words：concrete；efflorescence performance；microstructure

0 引言

混凝土泛碱作为工程实践中常见的质量问题，不仅影响建筑物的外观美观，更在一定程度上威胁着结构的耐久性与安全性[1]。（剩余7513字）