摘要
为阐明不同养护条件下粉煤灰基地质聚合物的变形机制和合理评价地质聚合物中ASR安全性,分别研究了常温和38℃湿气养护(>95%R.H.)、80℃1 mol/L NaOH溶液浸泡及150℃10%KOH溶液压蒸等养护条件对粉煤灰基地质聚合物变形行为的影响,并采用XRD、SEM研究了产物的组成和微观结构。结果表明:地质聚合物试体在不同养护条件下的化学反应和变形显著不同;(1)无外碱介质介入时,地质聚合物试体在所测龄期内均收缩。升高温度可加快地质聚合反应速率,缩短地质聚合产物结构达到稳定的时间;(2)高温养护和外碱介入,促进地质聚合产物由凝胶向沸石转变,可补偿聚合过程伴随的收缩,甚至呈现总体膨胀。采用适于OPC体系的高温、高碱快速检测AAR的检测方法评价地质聚合物体系的碱集料反应时需考虑基体的变形。
For exploring the deformation mechanism of geopolymer in various conditions and estimating ASR in geopolymer legitimately,effect of four different curing conditions（20 ℃ and 38 ℃ and relative humidity more than 95%,immersed in 1 mol/L NaOH solution at 80 ℃ and autoclaved in 10%KOH solution at 150 ℃） on the deformation behaviour of fly ash-based geopolymer were studied.The composition and microstructure of products were measured by XRD and SEM.The results showed that the geopolymer specimens experience different reaction processes and different deformation behaviours.（1） Geopolymer specimens cured without additional alkali conditions shrank in the whole period.The higher the curing temperature was,the faster the geopolymerazation process occured,and the less time when the matrixs structure come to stabilization.（2） High alkali solution and high temperature processing was favorable for the transformation of product structure into zeolite precursor or zeolite structure.The formation of zeolite precursor could compensate shrinkage.The deformation of the matrix when adopt the methods of using high alkali,high temperature to accelerate AAR in traditional OPC to estimate AAR in geopolymer should be considered.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2011年第6期1227-1232,共6页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金(No.51072080)
教育部科学技术研究重点资助项目(No.210079)
关键词
粉煤灰基地质聚合物
养护条件
变形行为
沸石先驱体
fly ash-based geopolymer
curing condition
deformation behaviour
zeolite precursor
