Surface modification of bamboo aggregates for enhanced cement mortar performance

Abstract The intensive extraction of natural sand and gravel has led to resource depletion and increasing environmental concerns, driving interest in renewable plant‐based alternatives such as bamboo. This study investigates the chemical modification of bamboo aggregates in cement mortar to improve interfacial compatibility and enhance mechanical performance. Six low‐impact, cost‐effective, and scalable surface treatments were evaluated: ACQ–polyacrylate, glycerol, silane, alkali, sodium silicate, and acid treatments. Microstructural characterizations focusing on interfacial features were conducted to assess their effects on aggregate–matrix bonding and the resulting composite properties. Compared with the unmodified mixture, mortars incorporating chemically modified bamboo aggregates exhibited notable improvements in mechanical performance, with flexural strength and splitting tensile strength increased by approximately 15% and 20%, respectively, depending on the modification method. Among them, low‐concentration acetic acid treatment achieved the greatest increases in flexural and splitting tensile strengths, whereas the AP method minimized compressive strength reduction. Considering mechanical performance, cost, and practical applicability, low‐concentration acetic acid emerged as a particularly effective and balanced modification strategy under the tested conditions. These findings provide guidance for the efficient utilization of bamboo and other plant‐based aggregates in cementitious composites and support the development of sustainable construction materials.