粉煤灰钙含量、细度对高性能混凝土性能影响研究

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中图分类号：TU528 文献标志码：A 文章编号：1005-8249（2025）06-0001-07

DOI：10.19860/j.cnki.issn1005-8249.2025.06.001

Abstract： To reduce the consumption of Portland cement in high - performance concrete（HPC）， 40% of the cement was replacedwithflyash of varying calcium contentand fineness.Theefectsof GradeIhigh-calcium flyash（HFA），lowcalcium flyash（LFA），and Class I flyash（I FA）on the compressive strength，chloride ion permeability coefficient，water absorptionrate，andcumulative hydration heat evolutionof HPC.Residual calcium hydroxide content wasanalyzedvia XRD. The results indicate that substituting 40% cement with HFA or LFA enables HPC production，with 9O - day compressive strength increasing by 8.6% and 13.8% respectively compared to the control group.HFA promotes early strength development，while LFA yields higherlong-termstrength.Theaditionofflyashimprovedthechlorideionpermeabilityresistanceandreducedthe Waterabsorptionrateof HPC，with fineness havingamore significant impactthancalciumoxidecontent.Flyash significantly reducedthe hydrationheatrelease，withLFAexhibitinglowerheatreleasethan HFA，andfinenessonlyafecting theearlyheatreleaserate.LFAcontained higheramorphous silicoaluminate glassphasethan HFA，enablingcompleteconsumptionofcement hydration calcium hydroxide to form C- （A） -S-Hgel ， resulting in the lowest residual calcium hydroxide content. These findings provide a basis for substituting cement with different types of fly ash.

Key words：flyash；calciumoxide；high-performanceconcrete；compresive strength；chlorideionpermeabilitycoeficient; hydration heat

0 引言

高性能混凝土（HPC）因其优异的力学性能、卓越耐久性、低渗透性、长服役寿命等特性，在现代混凝土建筑中发挥着重要作用[1]。（剩余9138字）