Flexural Behavior of Epoxy-Bonded Timber and the Influence of Steel Bar Reinforcement

Abstract

This study aimed to investigate the flexural behavior of epoxy-bonded timber and evaluate the influence of reinforcing with smooth round steel bars on structural performance. The variables studied included wood type, classified as hardwood (Redwood) and softwood (Pinewood), and epoxy types comprising high-density epoxy and low-density epoxy. All timber specimens had cross-sectional dimensions of 50×50 mm and a length of 760 mm according to ASTM D143 standard. The parameters evaluated included ultimate bending load, ultimate deflection, ultimate stiffness, and failure modes. The results indicated that reinforcement with smooth round steel bars combined with high-density epoxy significantly increased the ultimate bending load by 17–20% for hardwood and 39–124% for softwood compared to non-reinforced specimens. Reinforcement also increased the ultimate deflection by 24–37% in hardwood and 13–91% in softwood. High-density epoxy contributed to improved stiffness due to its excellent bonding characteristics. The results from this research can be effectively applied to the design and development of timber structures with enhanced structural performance and sustainability.