Size influence of laminated bamboo on tensile mechanical properties with the consideration of density

Laminated bamboo (LB), as a novel eco-friendly composite material with a high strength-to-weight ratio, has garnered increasing interest. However, there is a gap in comprehending the impact of size on the tensile properties of LB, particularly tensile strength and modulus. In contrast with conventional materials such as concrete and wood, which have specified specimen sizes and size effect factors to address performance variances linked to size, LB lacks such standards and references. To address this, seven groups of LB specimens of varying sizes were developed and tested to examine the impact of length, thickness, and sectional area on failure mechanisms and fundamental features, including density considerations. The findings demonstrate that size does not significantly influence the failure mode. Length exerts a smaller influence than thickness. When specimens are scaled up by a factor of two, tensile strength and modulus diminish to 82.86% and 88.38% of their initial values, respectively. Density significantly influences the relationships of tensile strength, modulus, and size effects. Consequently, size effect models incorporating both specific properties and the density-property relationship were developed.