Autoclaved aerated concrete (AAC) has low density, suitable compressive strength, and excellent thermal and sound insulation capacity for building non-bearing walls. However, porous AAC blocks usually have low flexural strength and thus are prone to cracking during service life. Herein, bamboo cellulose nanofibers (BCNF) were incorporated into AAC matrix to enhance mechanical strengths. The BCNF was further modified by 3-mercaptopropyl-trimethoxysilane (KH590) to improve the interfacial bonding between BCNF and AAC matrix. Results showed that the AAC with the addition of 0.3 wt% KH590-modified BCNF had 49.2% and 20.7% higher flexural strength and compressive strength than those without BCNF, respectively. AAC slurry belongs to a pseudoplastic fluid with a yield value, which can be described by Bingham rheological model. With the increase of shear rate, the stress of AAC slurry increased and the viscosity decreased exponentially. The interfacial bonding of BCNF/AAC-matrix was characterized by FTIR, XPS, NMR, and SEM analyses. It was confirmed that the siloxane groups of KH590 react with the hydroxyl groups of BCNF, thus grafting the BCNF with hydrophobic moieties and improving their interfacial adhesion with AAC matrix. In addition, granite powders collected from stone processing mill were utilized as a main component of AAC matrix. This study provides a feasible way of utilizing renewable materials and solid waste in preparing high-performance AAC as green building materials.

蒸压加气混凝土（AAC）密度低，抗压强度适中，保温隔音性能优良，适用于非承重墙体。然而，多孔加气砌块通常具有较低的抗弯强度，因此在使用寿命期间容易开裂。在此，将竹纤维素纳米纤维 (BCNF) 掺入 AAC 基质中以增强机械强度。BCNF 通过 3-巯基丙基三甲氧基硅烷 (KH590) 进一步改性，以改善BCNF 和 AAC 基质之间的界面结合。结果表明，添加 0.3 wt% KH590 改性 BCNF 的 AAC 的抗弯强度和抗压强度分别比没有 BCNF 的高 49.2% 和 20.7%。AAC浆料属于具有屈服值的假塑性流体，可用 Bingham 流变模型来描述。随着剪切速率的增加，AAC浆料的应力增加，粘度呈指数下降。通过FTIR 、XPS、NMR和SEM分析表征BCNF/AAC-基质的界面结合。证实 KH590 的硅氧烷基团与 BCNF 的羟基发生反应，从而使 BCNF 与疏水部分接枝并提高其与 AAC 基质的界面粘附性。此外，从石材加工厂收集的花岗岩粉末用作 AAC 基质的主要成分。本研究为利用可再生材料和固体废弃物制备高性能加气作为绿色建筑材料提供了一条可行的途径。