Ling Yifu, Wu Xionghua, Tan Kanghao, Zou Zhenjie
Key Laboratory of Disaster Prevention and Engineering Safety of Guangxi, School of Civil Engineering and Architecture, Guangxi University, Nanning 530004, China.
Guangxi Highway Detection Co., Ltd., Nanning 530004, China.
Materials (Basel). 2023 Mar 31;16(7):2809. doi: 10.3390/ma16072809.
Biochar (BC), a byproduct of agricultural waste pyrolysis, shows potential as a sustainable substitute material for ordinary silicate cement (OPC) in concrete production, providing opportunities for environmental sustainability and resource conservation in the construction industry. However, the optimal biochar dosage and fineness for enhancing concrete performance are still unclear. This study investigated the impact of these two factors on the mechanical and durability properties of biochar concrete. Compressive and flexural strength, carbonation resistance, and chloride ion penetration resistance were evaluated by varying biochar dosages (0%, 1%, 3%, 5%, 10%) and fineness dimensions (44.70, 73.28, 750, 1020 μm), with the 0% dosage serving as the control group (CK). The results showed that the addition of 1-3 wt% of biochar could effectively reduce the rapid carbonation depth and chloride diffusion coefficient of concrete. The compressive and flexural strength of BC concrete initially increased and then decreased with the increase in biocarbon content, BC with a fineness of 73.28 μm having the most significant effect on the mechanical strength of concrete. At the dosage of 3 wt%, BC was found to promote the hydration degree of cement, improving the formation of cement hydration products. These findings provide valuable insights for the development of sustainable and high-performance cement-based materials with the appropriate use of biochar as an additive.
生物炭（BC）是农业废弃物热解的副产物，在混凝土生产中作为普通硅酸盐水泥（OPC）的可持续替代材料具有潜力，为建筑业的环境可持续性和资源节约提供了机会。然而，提高混凝土性能的最佳生物炭用量和细度仍不明确。本研究调查了这两个因素对生物炭混凝土力学性能和耐久性的影响。通过改变生物炭用量（0%、1%、3%、5%、10%）和细度尺寸（44.70、73.28、750、1020μm）来评估抗压强度、抗折强度、抗碳化性能和抗氯离子渗透性能，其中0%用量作为对照组（CK）。结果表明，添加1-3wt%的生物炭可有效降低混凝土的快速碳化深度和氯离子扩散系数。BC混凝土的抗压强度和抗折强度随生物炭含量的增加先升高后降低，细度为73.28μm的生物炭对混凝土力学强度的影响最为显著。在3wt%的用量下，发现生物炭可促进水泥的水化程度，改善水泥水化产物的形成。这些发现为合理使用生物炭作为添加剂开发可持续高性能水泥基材料提供了有价值的见解。
