Bamboo is widely available and renewable. Using bamboo blocks to partially replace coarse aggregates in the production of concrete solid bricks shows promising application prospects in areas such as nonload-bearing wall materials. However, as a natural biomass material, bamboo squares have disadvantages such as susceptibility to decay, water absorption, swelling, and drying shrinkage, necessitating modification when used as concrete coarse aggregate. This study subjected raw bamboo squares to high-temperature carbonization. The compressive performance of concrete made with these carbonized bamboo squares was first tested and compared with concrete containing raw bamboo squares. Subsequently, both raw and carbonized bamboo squares were modified using conventional methods: polyvinyl alcohol (PVA) treatment, epoxy mortar (EM) treatment, epoxy resin (EPR) treatment, water glass (WG) treatment, and glutinous rice glue treatment. Modified bamboo block concrete specimens were prepared, and their compressive strengths were tested and compared. The results indicated that the compressive mechanical performance of carbonized bamboo block concrete consistently outperformed that of raw bamboo block concrete across all substitution rates. Specifically, the optimal modification method—using epoxy mortar (EM) encapsulation—significantly enhanced the mechanical properties. At a high volumetric replacement rate of 30%, the EM-modified carbonized bamboo concrete achieved a compressive strength of 27.79 MPa, which is 15.1% higher than that of identically treated raw bamboo concrete and far exceeds the standard MU7.5 grade requirements. These quantitative findings provide a solid experimental and theoretical basis for the high-value application of bamboo squares in sustainable concrete solid bricks.
Zhou et al. (Fri,) studied this question.