粉煤灰和硅灰取代率对碱矿渣混凝土力学性能影响分析  

Effect of Fly Ash and Silica Fume Contents on Mechanical Properties of Alkali-Activated Slag-Based Concrete

作　　者：夏冬桃 吴晨[1] 崔凯 吴方红 李彪 王煜 喻诗汀[1] 李耀威 XIA Dongtao;WU Chen;CUI Kai;WU Fanghong;LI Biao;WANG Yu;YU Shiting;LI Yaowei(School of Civil Engineering,Architecture,and Environment,Hubei University of Technology,Wuhan 430068,China;Key Laboratory of Intelligent Health Perception and Ecological Restoration of Rivers and Lakes,Ministry of Education,Hubei University of Technology,Wuhan 430068,China;School of Civil Engineering,Wuhan University,Wuhan 430072,China;School of Transportation,Civil Engineering&Architecture,Foshan University,Foshan 528225,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,湖北武汉430068 [2]湖北工业大学河湖健康智慧感知与生态修复教育部重点实验室,湖北武汉430068 [3]武汉大学土木建筑工程学院,湖北武汉430072 [4]佛山大学交通与土木建筑学院,广东佛山528225

出　　处：《西南交通大学学报》2024年第5期1113-1122,共10页Journal of Southwest Jiaotong University

基　　金：国家自然科学基金项目(52208152,52308248)。

摘　　要：为研究粉煤灰和硅灰取代率对碱矿渣混凝土(AASC)性能的影响,通过凝结时间和基本力学性能试验,探究AASC凝结时间、立方体抗压强度、立方体劈拉强度、抗折强度和弹性模量的变化规律,基于试验结果,采用回归分析的方法,建立立方体劈裂抗拉强度、抗折强度以及弹性模量与立方体抗压强度的转换关系方程,并结合AASC的微观形貌和物相组成,揭示粉煤灰和硅灰对AASC性能的影响机理.结果表明:粉煤灰和硅灰的取代可延长AASC的凝结时间;AASC力学性能指标随粉煤灰和硅灰取代率的增大而呈现出先增强后减弱的趋势,粉煤灰和硅灰最优取代率分别为20%和10%;提出的AASC立方体劈拉强度、抗折强度以及弹性模量的经验公式拟合精度高;粉煤灰(取代率≤20%)和硅灰(取代率≤10%)的取代促进了AASC的水化反应,使微观形貌更为密实.In order to study the effect of fly ash and silica fume contents on the properties of alkali-activated slagbased concrete(AASC),the changes in setting time,cubic compressive strength,cubic splitting tensile strength,flexural strength,and elastic modulus of AASC were investigated by conducting tests on setting time and basic mechanical properties.Based on the test results,a regression analysis method was used to establish the conversion relationship equation of cubic splitting tensile strength,flexural strength,and elastic modulus with cubic compressive strength,and the effect of fly ash and silica fume on the properties of AASC was revealed according to the microstructure and phase composition.The results show that the fly ash and silica fume can prolong the setting time of AASC;the mechanical property indicators of AASC tend to strengthen and then weaken with the increase in the contents of fly ash and silica fume,and the optimal contents of fly ash and silica fume are 20% and10%,respectively.The proposed empirical formulae for cubic splitting tensile strength,flexural strength,and elastic modulus of AASC have a high fitting precision.The appropriate contents of fly ash(silica fume≤20%)and silica fume(silica fume≤10%) can promote the hydration reaction of AASC and the denser microstructures.

关 键 词：碱激发矿渣混凝土 粉煤灰 硅灰 力学性能 微观结构 

分 类 号：TU528[建筑科学—建筑技术科学]