高掺量粉煤灰混凝土力学性能试验研究

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中图分类号：TU528.01 文献标志码：A 文章编号：1005-8249（2025）02-0049-05

DOI：10.19860/j.cnki.issn1005-8249.2025.02.009

Abstract：Tostudythemechanical propertiesofhighcontentflyashconcrete，concretespecimenscontaining dierent proportions of fly ash （ 40 % ， 50 % ， 60 % ， 70 % ）and steel fibers（volume fractions of 0 . 2 5 % ， 0 . 5 0 % ， 0 . 7 5 % ， 1 % ） wereprepared andtestedunder simulatedenvironmental conditions.Analyzethe mechanical propertiesof high content flyash concrete bytesting thecompresivestrength，spliting tensilestrength，drying shrinkagerate，and microstructureof the specimens.Theresultsshow that thecompressivestrength ofconcrete decreases most significantlywhentheflyashcontent is between 40 % and 5 0 % ；When the volume fraction of steel fibers increases to 1 % ，the splitting tensile strength has increased by 2 4 . 4 % compared with that of the concrete without steel fibers，and the maximum flexural strength reaches 6 . 2 M P a ，an increase of 2 9 . 2 % compared to the original strength；The drying shrinkage rate of concrete shows a trend offirst decreasing and then increasing with the increase of fly ash content. When the content increases to 70 % ，the shrinkage rate decreases by 1 2 . 2 2 % compared to the benchmark concrete，and the porosity of the concrete slightly increases to about 8 % .It can be concludedthattheappropriateproportionofflyashandsteelfiberscansignificantlyimprovethetensilestrengthandflexural strengthofconcrete，optimizeitsdryingshrinkageperformanceandporestructure，therebyenhancingthemechanicalproperties and compactness of concrete.

Key words： high admixture；fly ash；concrete；steel fiber；mechanical properties

0 引言

高性能混凝土因其高强度、高力学性和高可靠性，在桥梁、隧道、高层建筑及医院等公共建筑得到广泛应用。（剩余5333字）