Open Collections

Pineda, Hugo

University of British Columbia

Engineered bamboo composite (EBC) mats must be pressed to consolidate, cure the resin, and densify the product. This consolidation process underpins the final product quality and properties, the volumetric output, and duration of the manufacturing process. This dissertation aims to develop a model that simulates the consolidation of EBC mats using a multiscale approach. The transverse compression behavior of mats is predicted based on the compression behavior of bamboo material and the distribution of bamboo elements within the mats. The transverse compression behavior of Moso Bamboo was studied to model the consolidation of EBC mats. The bamboo culm wall matrix (parenchyma cells, vessels, and sieve tubes) resembles a closed cell foam in transverse compression characterized by high-density variation among specimens. It, therefore, plays an essential role in the bamboo material's overall density, compression behavior, and modulus. Tissue density and its natural fiber-reinforced composite structure influence this behavior and moduli. A refined mathematical model is presented which captures the non-linear stress-strain behavior of bamboo considering these characteristics. Most EBCs exhibit variability from variations in bamboo element geometry and the manual mat formation process. Based on object collision physics, a computational model for EBC mat formation is presented in terms of bamboo element spatial arrangement and horizontal density distribution. The model was calibrated and validated using experimental data from commercial panels and simulated element deposition, 3D density distribution, and variability. Parametric analyses showed that element and panel thickness, element width, and width taper significantly affect density variability and mat uniformity. Combining the bamboo compression and mat formation models, a holistic model for consolidating EBC mats is presented. The model predicts the stress-strain behavior of mats during consolidation, as well as the changes in porosity and relative contact area. EBCs require as much as three times more pressure and higher densification to achieve the same contact area than commercial engineered wood products, and the pressure required is affected by the distribution of the bamboo elements in the mat. Although developed for EBCs with non-structured mats, the model can be modified to simulate a range of products from different bamboo or wood species.

Text

2024-05-16

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/88322

Forestry

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/