Cellular structure and property relationship of bamboo under transverse compression

Abstract

Transverse compression of bamboo occurs during manufacturing of engineered bamboo products and densified bamboo, as well as in service under compressive-loading in structures. This study investigates the transverse compression behavior of Moso bamboo and the relationship of its compression modulus with density, and provides microscopic observations of the changing cellular structure during transverse loading. When compared to softwood of same density, bamboo shows higher compression modulus and yield strength. Bamboo’s matrix (parenchyma cells, vessels and sieve tubes) resembles a closed cell foam in transverse compression, presenting high density variation among specimens and plays an important role in its overall density, behavior and compression modulus. Bamboo’s behavior and compression moduli are also influenced by tissue density and its natural fiber reinforced composite structure. A refined model is required and presented which captures the non-linear stress-strain behavior of bamboo considering these characteristics. The model works in a range of densities in Moso bamboo and provides accurate prediction of its transverse compression behavior and magnitude.