偏高岭土基地质聚合物的配合比及养护条件对其力学性能及凝结时间的影响研究

Study on Effect of Mix and Curing Conditions on the Mechanical Properties and Setting Time of Metakaolin-Based Geopolymer

本文以煅烧得到的偏高岭土为原料,以氢氧化钠与水玻璃作为复合碱性激发剂制备地质聚合物,系统考察了氢氧化钠、硅酸钠和水等组分含量的变化,对地质聚合物力学性能及凝结时间的影响;以及在最优激发剂配合比的选择下,不同的养护条件对于地聚物力学性能的影响。研究结果表明:地聚物力学性能及凝结时间随氢氧化钠用量增加先提高后降低;且影响作用趋于一致。水的用量对地聚物的强度基本无影响,但对凝结时间影响较大。适当提高养护温度可以提高地质聚合物的强度,适当延长养护时间可以提高地质聚合物的早期强度。

In this present paper,taking the calcined kaolin as the raw material,Geopolymer composites were prepared by Alkali composite activator which consists of sodium hydroxide and sodium silicate. By measuring the compressive strength and the setting time of geopolymer and by changing the content of each component in activator,the effects on the mechanical properties and setting time of metakaolinbased geopolymer have been systematically discussed. Besides,under the selection of the optimal ratio of activator,the effects of different curing conditions on the properties of geopolymers have also been studied. The results show that the amount of sodium hydroxide had the largest influence in the mechanical properties of geopolymers and setting time,and the influence tends to be consistent. However,the amount of water had no effect on the strength of geopolymer,but it had a larger impact on the setting time. Therefore,an appropriate increase in curing temperature can improve the strength of geopolymer and the appropriate extension in curing time can improve the early strength of geopolymer. During theengineering applications,different activator component and curing conditions can be adjusted according to different uses.