矿渣掺量对热养护粉煤灰基地聚物收缩和抗压强度的影响及机理分析  

Effect and Mechanism Analysis of Slag Content on Shrinkage and Compressive Strength of Thermal Curing Fly Ash-Based Geopolymer

作　　者：郭红丽 白鹏翔 洪淼 朱飞鹏[1] 胡丰[1] 雷冬[1,2] GUO Hongli;BAI Pengxiang;HONG Miao;ZHU Feipeng;HU Feng;LEI Dong(College of Mechanics and Materials,Hohai University,Nanjing 211000,China;Suzhou Research Institute,Hohai University,Suzhou 215100,China)

机构地区：[1]河海大学力学与材料学院,南京211000 [2]河海大学苏州研究院,苏州215100

出　　处：《硅酸盐通报》2023年第12期4389-4398,4426,共11页Bulletin of the Chinese Ceramic Society

基　　金：河海大学大型仪器设备共享基金(GX202206B);苏州市科技发展计划(SYC2022080)。

摘　　要：本文通过数字图像相关(DIC)方法研究了0%、10%、20%、30%、40%、50%六种矿渣掺量(质量分数,下同)对粉煤灰基地聚物(FAGP)混凝土热养护过程中收缩的影响,测试了热养护后混凝土和净浆的抗压强度,并且结合同步热分析(TGA-DSC)、X射线衍射(XRD)和扫描电子显微镜(SEM)对微观机理进行了分析。结果表明:随着矿渣掺量的增加,FAGP的收缩量和收缩速率均先减小后增大,抗压强度先增大后减小,水化程度增大,微裂缝数量增加;当矿渣掺量为40%时,FAGP混凝土的收缩量最小,抗压强度最大;当矿渣掺量较低时,地聚物水化程度小,微裂缝少,地聚物收缩的主要原因是热养护初期的弹性模量较低;当矿渣掺量较高时,地聚物水化程度大,微裂缝较多,地聚物收缩主要由较强烈的化学反应引起。The effects of six slag dosages of 0%,10%,20%,30%,40%and 50%(mass fraction,the same below)on the shrinkage of fly ash-based geopolymer(FAGP)concrete during thermal curing process were studied with digital image correlation(DIC)method.The compressive strength of concrete and paste after thermal curing were tested,and the microscopic mechanism was analyzed by combining simultaneous thermal analysis(TG-DSC),X-ray diffraction(XRD)and scanning electron microscope(SEM).The results show that with the increase of slag content,the total shrinkage and shrinkage rate of FAGP first decrease and then increase,the compressive strength increases first and then decreases,the hydration degree increases,and the number of microcracks increases.When the slag content is 40%,FAGP concrete has the smallest shrinkage and the highest compressive strength.When the slag content is low,the hydration degree of the geopolymer is small,and there are fewer microcracks.At this time,the main reason for the shrinkage of the geopolymer is the lower elastic modulus at the beginning of thermal curing.When the slag content is high,the hydration degree of the geopolymer is high,and there are many microcracks.At this time,the shrinkage deformation of the geopolymer is mainly caused by a large degree of chemical reaction.

关 键 词：数字图像相关方法 矿渣 粉煤灰基地聚物 热养护 收缩 抗压强度 

分 类 号：TU528.01[建筑科学—建筑技术科学]