Abstract In this study, rice husk ash (RHA)-based reactive filler was used in ultra-high performance concrete (UHPC) to improve mechanical properties without heat-treatment. This strategy replaces inert quartz filler with the reactive RHA filler, to increase the amorphous silica content while maintaining the physical role of the micron-sized quartz filler. Due to the high porosity of RHA, internal curing is effective, which promotes the hydration reaction over a long period of time. Experimental results show an outstanding strength around 200 MPa after 91 days, under ambient conditions (20 °C and 60% relative humidity). This was possible due to the promotion of pozzolanic reaction by additional water and amorphous silica provided by the porous (i.e., internal curing effect) and reactive filler, respectively; hence, the volume of capillary pores was reduced. The result reported herein will further promote the utilization of agricultural byproduct for the development of reactive RHA-based construction materials.

中文翻译：

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稻壳灰作为活性填料在超高性能混凝土中的应用

摘要 在这项研究中，稻壳灰（RHA）基活性填料用于超高性能混凝土（UHPC）以提高机械性能而无需热处理。该策略用反应性 RHA 填料代替惰性石英填料，以增加无定形二氧化硅含量，同时保持微米级石英填料的物理作用。由于 RHA 的高孔隙率，内部固化是有效的，这促进了长时间的水合反应。实验结果表明，在环境条件（20°C 和 60% 相对湿度）下，91 天后具有约 200 MPa 的出色强度。这是可能的，因为分别由多孔（即内部固化效果）和反应性填料提供的额外水和无定形二氧化硅促进了火山灰反应；因此，毛细孔体积减少。本文报告的结果将进一步促进农副产品在反应性 RHA 基建筑材料的开发中的利用。