摘要
在自密实混凝土中加入矿物掺合料,可以改善混凝土的力学性能及耐久性,降低混凝土的粘度,提升混凝土中后期的抗压强度,达到降本增效、提升混凝土性能的目的。本文基于不同的矿物掺合料种类和配合比,研究其对自密实混凝土各项性能参数的影响,结果表明:随着粉煤灰掺量的增加,混凝土的扩展度逐渐增加,当粉煤灰掺量超过20%时,混凝土的扩展度基本不变;随着矿粉掺量的增加,混凝土的扩展度增长幅度较小,当矿粉掺量超过15%时,混凝土静置后出现泌水现象;当粉煤灰掺量为20%、矿粉掺量为15%时,混凝土的坍落度为270 mm,扩展度为630 mm,混凝土流动性能良好,整体松软,静置无泌水现象,其扩展度达到500 mm所需的时间为6.5 s,28 d抗压强度48.9 MPa,28 d收缩性能良好,抗碳化性能较好。
Adding mineral admixtures to self compacting concrete can improve its mechanical properties and durability,reduce its viscosity,enhance its compressive strength in the middle and later stages,and achieve the goal of reducing costs,increasing efficiency,and enhancing concrete performance.This article studies the influence of different types and proportions of mineral admixtures on the performance parameters of self compacting concrete.The results show that with the increase of fly ash content,the expansion of concrete gradually increases.When the fly ash content exceeds 20%,the expansion of concrete remains basically unchanged;with the increase of mineral powder content,the degree of expansion of concrete increases relatively small.When the mineral powder content exceeds 15%,there is bleeding phenomenon in the concrete after it is left to stand.When the fly ash content is 20%and the mineral powder content is 15%,the slump of the concrete is 270 mm and the expansion is 630 mm,it has good flowability,overall softness,and no bleeding phenomenon occurs when left standing,the time required for its expansion to reach 500 mm is 6.5 s,the compressive strength at 28 days is 48.9 MPa,the shrinkage performance and carbonation resistance at 28 days are good.
出处
《混凝土世界》
2024年第6期39-42,共4页
China Concrete
关键词
自密实混凝土
矿物掺合料
流动性
力学性能
收缩性能
碳化性能
Self compacting concrete
mineral admixtures
liquidity
mechanical properties
shrinkage performance
carbonization performance
作者简介
第一作者:王冲,1988年生,硕士,工程师,主要从事无机非金属相关研究工作,E-mail:353966425@qq.com。
