低温烧制稻壳灰活性及其混凝土性能研究  

Study on the activity of rice husk ash and its concrete fluidity and mechanical properties

作　　者：连跃宗[1,2] 庄一舟 田尔布 曾武华[1,2] LIAN Yuezong;ZHUANG Yizhou;TIAN Erbu;ZENG Wuhua(College of Civil Engineering,Sanming University,Sanming 365004,China;Fujian Provincial Key Laboratory of Engineering Materials and Structure Reinforcement,Sanming 365004,China;College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310023,China)

机构地区：[1]三明学院建筑工程学院,福建三明365004 [2]福建省工程材料与结构加固重点实验室,福建三明365004 [3]浙江工业大学土木工程学院,浙江杭州310023

出　　处：《浙江工业大学学报》2022年第6期659-663,共5页Journal of Zhejiang University of Technology

基　　金：福建省中青年教师教育科研项目(JAT190699,B201912);福建省科技厅社会发展引导性(重点)项目(2019Y0044)。

摘　　要：不同温度下烧制的稻壳灰(RHA)整体活性不同,RHA中的SiO活性不仅是决定整体活性的主要因素,而且直接影响着RHA在混凝土应用。通过马弗炉在不同温度下烧制RHA来研究RHA活性,并用RHA取代部分水泥,研究其对RHA混凝土性能影响。实验结果表明:马弗炉烧制RHA最佳时间为80 min,其SiO质量分数超过90%;SiO发生了晶型转变(晶变温度为650~800℃),随着烧制温度继续升高,RHA活性逐渐变低,原有的网状蜂窝结构逐渐被破坏;不同温度烧制的RHA的电导率有不同的表现,但是pH值整体呈下降趋势;RHA颗粒的滚珠效应大于因比表面积增大而增加吸水效应,坍落度随着RHA的比表面积增大而增大;随着粉磨持续进行,RHA的颗粒填充效应和团聚现象逐渐增强,RHA的比表面积减小,RHA的滚珠效应作用降低,坍落度下降;在800℃下烧制的RHA,经过不同时间的粉磨,其混凝土的28 d抗压强度与RHA的比表面积呈正相关。The overall activity of rice husk ash(RHA)sintered at different temperatures is different.It is found that the SiO_(2) activity in RHA is the main factor that determines the overall activity of RHA,and directly affects the application of RHA in concrete.In this paper,a muffle furnace is used to combust RHA at different temperatures,and the activity of RHA is studied.RHA replaces part of the cement to study its effect on the performance of RHA concrete.The results show that the optimal firing time of RHA using the muffle furnace is 80 min,and the SiO_(2) mass fraction of RHA exceeds 90%.The crystalline transformation of SiO_(2) occurs(the crystallization temperature is from 650 to 800℃).With the increase of sintering temperature,the activity of RHA gradually decreases,and the original reticular honeycomb structure is gradually destroyed.The conductivity of RHA sintered at different temperatures is different,but the pH value shows a downward trend.The ball effect of RHA particles is greater than the increase in water absorption due to the increase in surface area.The slump increases as the specific surface area of RHA increases.As the grinding continues,the particle filling effect and agglomeration phenomenon of RHA strengthens.As a result,the specific surface area and ball effect of RHA decrease and the slump reduces.RHA sinters at 800℃.After different times of grinding,the 28 d compressive strength of concrete is positively correlated with the specific surface area of RHA.

关 键 词：稻壳灰 马弗炉 活性 混凝土 

分 类 号：U414.01[交通运输工程—道路与铁道工程]