Kim Junho, Fumino Hikaru, Kanematsu Manabu
Department of Architecture, Faculty of Science and Technology, Tokyo University of Science, Noda City 278-8510, Japan.
National Institute of Technology (KOSEN), Oyama College, Oyama City 323-0806, Japan.
Materials (Basel). 2024 Dec 25;18(1):21. doi: 10.3390/ma18010021.
A fundamental study has been conducted on the effective utilization of rice husk ash (RHA) in concrete. RHA is an agricultural byproduct characterized by silicon dioxide as its main component, with a content of 90% or more and a porous structure that absorbs water during mixing, thereby reducing fluidity. The quality of RHA varies depending on the calcination environment; however, the effect is not consistent. In this study, the pore structure was modified, and fluidity was improved by adjusting the particle size of the RHA. From a quality control perspective, this study aims to classify grades using Luxan values. While the characterization of RHA is based on Luxan values, the methodology for measuring its hydration response has not been reviewed. The test methods used in this study are as follows. To test the raw materials, density, specific surface area, XRF, SEM, and isothermal adsorption-desorption curves were measured, and fluidity was measured in fresh mortar. In a hardened mortar, compressive strength and drying shrinkage length change rate were measured. In addition, XRD and TG were measured for specimens after the compressive strength test. The selective dissolution method was used to measure the hydration rate. By adjusting the particle size of RHA to 45 µm, fluidity was enhanced. The relationship between the Luxan value and the basic properties of the mortar indicates that higher Luxan values correspond to greater compressive strength and drying shrinkage. We believe that the method used in this experiment can be used to quantify RHA.
对稻壳灰（RHA）在混凝土中的有效利用进行了一项基础研究。RHA是一种农业副产品，其主要成分是二氧化硅，含量在90%以上，具有多孔结构，在搅拌过程中会吸水，从而降低流动性。RHA的质量因煅烧环境而异；然而，其效果并不一致。在本研究中，通过调整RHA的粒径来改善孔隙结构并提高流动性。从质量控制的角度来看，本研究旨在使用卢克斯值对等级进行分类。虽然RHA的表征基于卢克斯值，但其水化反应的测量方法尚未得到审查。本研究中使用的测试方法如下。为了测试原材料，测量了密度、比表面积、X射线荧光光谱（XRF）、扫描电子显微镜（SEM）和等温吸附-脱附曲线，并在新鲜砂浆中测量了流动性。在硬化砂浆中，测量了抗压强度和干燥收缩长度变化率。此外，在抗压强度试验后对试件进行了X射线衍射（XRD）和热重分析（TG）。采用选择性溶解法测量水化速率。通过将RHA的粒径调整到45μm，流动性得到了提高。卢克斯值与砂浆基本性能之间的关系表明，卢克斯值越高，抗压强度和干燥收缩越大。我们认为本实验中使用的方法可用于量化RHA。
