硅灰掺量对混凝土性能的影响

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DOI：10.19860/j.cnki.issn1005-8249.2025.04.005

WENG Yalian， SUN Haiyan， LIANG Rongchuang， GAO Yuchang（College of Water Conservancy， Yunnan Agricultural University，Kunming 65O2O1，China）

Abstract：To studytheinfluenceof silica fumeonthe workability，mechanical properties anddry shrinkageof concrete，we investigatedtheefectsofsilicafumedosageonthefluidity，compressvestrength，splitingtensilestrengthanddryshrinkage rateof concreteunderdiferentwater-binderratios.Theresearchresultsshowthatthefluidityofconcretedecreasesgradualy withtheincreaseofsilicafumedosageunderboth water-binderratios，andtheefectismoresignificantinthewater-binder ratioof0.45group.Theincorporationofsilicafumeenhances thecompresiveandspliting tensilestrengthofconcretewith diferent water-binderratios.Specifically，comparedwith thereferencegroup，whenthewater-binderratioisO.45，the 28 days compressive and splitting tensile strength with 10% silica fume dosage increase by 18.1% and 14.8% ， 21.2% and （20 20.4% respectively.With the increaseof silica fume dosage，thedry shrinkage rate ofconcreteunder both water-binderratios increases.Compared with the water-binderratioofO.45group，thedryshrinkagerateofconcreteis higher whenthe water binder ratio is O.6O. The highest drying shrinkage rate was observed at9O days，with an increase of 29.5% and 25.1% compared to thebaseline group，respectively.Provideareference fortheoptimized designof high-performance silica fumeconcrete.

Key words： silica fume； dosage； water binder ratio； mechanical properties； drying shrinkage

0 引言

混凝土是现代建筑工程中的核心材料，其性能的优劣直接影响到工程结构的安全性和耐久性[1]硅灰（SF）作为具有极高火山灰活性的矿物掺合料，因其极细的颗粒和较高的 SiO2 含量，拥有较大的比表面积，可以有效地填充到水泥颗粒的孔隙之间，增加浆体的密实程度，从而有效阻止了有害物质的进入与扩散，显著改善混凝土的微观结构，被广泛应用于改善混凝土性能的领域[2-4]。（剩余7306字）