摘要
采用XRD、热分析、扫描电镜和抗压强度等方式,研究了水化硅酸镁(M-S-H)在不同煅烧温度下(200℃、500℃、700℃和900℃)脱水相组成和再水化后的产物、微观结构变化及力学性能再生性。实验结果表明:煅烧温度较低时M-S-H脱水相反应产物主要为MgO、Mg(OH)_(2)、M-S-H凝胶与少量硅酸镁结晶相,随着煅烧温度的升高,试样水分蒸发,产物发生转变,Mg(OH)_(2)和M-S-H凝胶含量减少,MgO、MgSiO_(3)和Mg_(2)SiO_(4)含量增加。900℃左右M-S-H凝胶已经消失,此时反应产物活性最低。对脱水相再水化产物进行研究,M-S-H脱水相发生了再水化,产物得到了恢复,养护至一定龄期的试样结构致密并具备一定的抗压强度。
XRD,thermal analysis,scanning electron microscopy and compressive strength were used to evaluate the composition of dehydrated phase,the product after rehydration,microstructure change and mechanical properties regeneration of MgO-SiO_(2)-H_(2)O system at different calcination temperatures(200℃,500℃,700℃and 900℃).The experimental results show that the reaction products of M-S-H dehydration phase with low calcination temperature are mainly MgO,Mg(OH)_(2),M-S-H gel,and a little magnesium silicate crystal phase.As the calcination temperature increases,the moisture in the sample evaporates and the product changes.The content of Mg(OH)2 and M-S-H gel decreased,and the content of MgO,MgSiO_(3)and Mg_(2)SiO_(4)increased.M-S-H gel has not been detected at about 900℃,and the activity of the reaction product is the lowest.It is found that the product has been recovered.The structure of the sample cured to a certain age is compact and has a certain compressive strength.
作者
李兆恒
周仁琦
马玉玮
LI Zhaoheng;ZHOU Renqi;MA Yuwei(Guangdong Research Institute of Water Resources and Hydropower, Guangzhou 510635,China;Guangdong Provincial Engineering Research Center for Water Conservancy Advanced Material and Structure, Guangzhou 510635,China;China Power Construction Group Hainan Electric Power Design and Research Institute Co., Ltd., Haikou 571100, China;Guangzhou University, Guangzhou 511400, China)
出处
《广东水利水电》
2022年第7期1-7,共7页
Guangdong Water Resources and Hydropower
关键词
水化硅酸镁
脱水相
再水化
hydrated magnesium silicate
dehydrated phase
rehydration
