Constitutive Material Model for the Compressive Behaviour of Engineered Bamboo

Abstract

The mechanical properties of the structural components (i.e., columns and beams produced from engineered bamboo products), such as, bamboo scrimber (also known as parallel bamboo strand lumber, PBSL) and Laminated Bamboo Lumber (LBL), have attracted considerable attention from researchers in recent years. In previous studies, researchers reported on the stress-strain behaviour of bamboo scrimber, LBL and glue laminated bamboo under compression and proposed some empirical and semi-empirical models, based on their individual studies. However, a generic constitutive model for engineered bamboo products is still not available. The compressive stress-strain curves of bamboo scrimber and LBL are reported to show a similar behaviour with three distinct stages i.e., a linear elastic stage followed by a nonlinear plastic stage and a plateau. As part of the current study, the previously proposed models for bamboo scrimber were carefully studied and all available material test results on engineered bamboo were used to develop a generic constitutive model, based on the Ramberg-Osgood (RO) formulation considering its suitability to capture its material nonlinearity. Based on the test results, it was observed that 1% proof stress can be used in a compound RO model to predict an accurate material response for bamboo scrimber. The proposed modelling technique has also been applied to predict the compressive behaviour of LBL. This paper proposes the RO coefficients for both bamboo scrimber and LBL that can be used to develop accurate nonlinear models for engineered bamboo products.

Mechanical properties of laminated bamboo lumber N-finity according to ISO 23478-2022

“…The first one is a linear elastic behaviour up to the yield point marked as F c,90,max followed by a nonlinear behaviour with plastic deformation region to reach a peak point identifies as a maximum applied load F max , and finally the descending and rupture region can be identified. This supports the elastic-plastic compression model of LBL proposed previously [10,21]. The maximum compression displacement reached less than 16 mm for parallel-tograin direction, whereas it was about 19 and 10 mm for perpendicular-to-grain tangential and radial directions, respectively.…”

Durability Evaluation of Outdoor Scrimbers Fabricated from Superheated Steam-Treated Bamboo Fibrous Mats

“…With great concern that climate change is threatening the development and survival of human beings, carbon-negative materials are being developed to nullify embodied CO 2 emissions, in the meantime transforming constructions into net carbon storage structures on the basis of the life cycle [ 1 ]. Among them, bamboo scrimber is the most attractive one for structural applications [ 2 ]. Bamboo scrimber is produced by laminating the mechanically rolled bamboo (called bamboo fibrous mat) into a dense block in the presence of phenolic resin [ 3 ].…”