高摻量粉煤灰混凝土力學(xué)性能試驗(yàn)研究

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中圖分類號(hào):TU528.01 文獻(xiàn)標(biāo)志碼:A 文章編號(hào):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強(qiáng)度、高力學(xué)性和高可靠性,在橋梁、隧道、高層建筑及醫(yī)院等公共建筑得到廣泛應(yīng)用。(剩余5333字)