ABSTRACT

The heat curing process using an electric oven has been generally applied for curing geopolymer material as it accelerates strength development. However, a microwave curing process is an alternative approach to obtain a shorter heat curing process. This paper focuses on the strength development and required curing duration of a cellular lightweight geopolymer mortar using a microwave-assisted curing process. Other curing approaches, namely (i) room curing process, (ii) typical oven curing process, and (iii) microwave curing process, were also comparatively examined. Bottom ash was used as light-fine aggregate to replace sand by 0%, 25%, 50%, 75%, and 100%. The results revealed that replacing 25% of the sand with bottom ash provided the optimal strength and low density for all mixtures. A 28-day age strength of 12.27 MPa was achieved by the microwave-assisted curing process, while a strength of 5.77 MPa was achieved by the typical oven curing process. The microwave-assisted curing process could significantly improve the early strength development and reduce both the overall curing period and energy consumption by around 75% compared to a typical oven curing process. This approach could be applied as an alternative geopolymer synthesis for the development of environmental-friendly construction material for lightweight applications.

摘要

使用电炉的热固化过程通常用于固化地质聚合物材料，因为它可以加速强度发展。然而，微波固化过程是获得较短热固化过程的替代方法。本文重点介绍了使用微波辅助固化过程的多孔轻质地质聚合物砂浆的强度发展和所需的固化时间。其他固化方法，即 (i) 室温固化过程、(ii) 典型的烘箱固化过程和 (iii) 微波固化过程，也进行了比较检查。底灰用作轻细骨料，分别以0%、25%、50%、75%和100%的比例代替砂。结果表明，用底灰代替 25% 的沙子为所有混合物提供了最佳强度和低密度。28 天龄强度为 12。微波辅助固化工艺达到了 27 MPa，而典型的烘箱固化工艺达到了 5.77 MPa。与典型的烘箱固化工艺相比，微波辅助固化工艺可以显着改善早期强度发展，并将整体固化时间和能耗降低约 75%。这种方法可用作替代地质聚合物合成，用于开发轻质应用的环保建筑材料。