Effect of slenderness ratio on axial compression behavior of circular wood columns strengthened with high-performance bamboo-based composites

Developing sustainable high-performance bamboo-based composites (HPBBC) with carbon sequestration benefits as reinforcement material is of great significance in promoting the application of HPBBC and securing ancient wooden buildings. Available column reinforcement methods have damage characteristics, which are unsuitable to be applied in ancient wooden columns because the ancient building needs to be preserved in the current conditions. The wooden column was bound with HPBBC and spaced steel strips to achieve damage-free strengthening. The slenderness ratio is an essential factor affecting the mechanical properties of wood poles, which is significant to be studied. The effect of the slenderness ratio on the axial compression behavior of circular wood columns strengthened with HPBBC was investigated in this study. The test results showed that the slenderness ratio significantly influences the failure mode, load-bearing capacity, and deformability of strengthened circular wood columns. The typical failure mode of short columns was a crushing failure, while the long columns were buckling failures. The load-carrying capacity and longitudinal strain of strengthened circular timber columns decrease significantly with increasing slenderness ratio. The lateral displacements or buckling appearance increases significantly with the increasing slenderness ratios of the strengthened timber column. A load-bearing capacity formula was proposed to predict the load capacity of strengthened circular wood columns based on their axial compression damage characteristics. The error between the calculated and tested results is less than 8.2 %.