养护环境对偏高岭土基地聚物性能及微观结构的影响  

Effect of Curing Environment on Properties and Microstructure of Metakaolin Based Geopolymers

作　　者：黄大建 王治武 唐文捷 张全超 强小虎 HUANG Dajian;WANG Zhiwu;TANG Wenjie;ZHANG Quanchao;QIANG Xiaohu(School of Materials Science and Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学材料科学与工程学院,兰州730070

出　　处：《硅酸盐通报》2024年第4期1463-1471,共9页Bulletin of the Chinese Ceramic Society

基　　金：固体废物处理与资源化教育部重点实验室开放课题(22kfgk04)。

摘　　要：为了探究养护环境对偏高岭土基地聚物干缩开裂特性和力学性能的影响,以不同养护环境为参数,系统研究了不同养护环境对偏高岭土基地聚物性能(抗压强度、收缩)和微观结构的影响。结果表明:温度交替变化环境(冻融循环)对偏高岭土基地聚物的结构影响较大,不利于偏高岭土基地聚物材料性能的发展;低湿度环境有利于体系中水分子排出,从而使形成的凝胶相更致密,有利于抗压强度的发展,但使干缩率和孔隙率增加。在各种养护环境中,干燥养护(温度(20±0.5)℃,湿度(50±5)%)条件下的试样28 d抗压强度达到73.94 MPa,较标准养护(温度(20±0.5)℃,湿度不低于95%)条件下的试样增长了68.77%,28 d干缩率为237.5×10^(-4),孔隙率达到最高(45.73%)。In order to explore the influence of curing environment on the drying shrinkage-cracking characteristics and mechanical properties of metakaolin based geopolymers,the effects of different curing environments on properties(compressive strength,shrinkage)and microstructure of metakaolin based geopolymers were studied systematically.The results indicate that alternating temperature changes(freeze-thaw cycles)have a significant impact on the structure of metakaolin based geopolymers,which is not conducive to the development of metakaolin based geopolymer material properties.Low humidity is conducive to the elimination of water molecules in the system,thus forming a more compact gel phase,which is conducive to the development of compressive strength,but increases the drying shrinkage rate and porosity.In various curing environments,the compressive strength of specimens under dry curing(temperature(20±0.5)℃,humidity(50±5)%)reaches 73.94 MPa at 28 d,an increase of 68.77%compared to the specimens under standard curing(temperature(20±0.5)℃,humidity not lower than 95%),and the drying shrinkage rate at 28 d is 237.5×10^(-4),with a maximum porosity of 45.73%.

关 键 词：地聚物 养护环境 偏高岭土 孔隙率 干缩率 

分 类 号：TB321[一般工业技术—材料科学与工程]