Thermal conductivity of engineered bamboo composites

Abstract

Here we characterise the thermal properties of engineered bamboo panels produced in Canada, China, and Colombia. Specimens are processed from either Moso or Guadua bamboo into multi-layered panels for use as cladding, flooring or walling. We utilise the transient plane source method to measure their thermal properties and confirm a linear relationship between density and thermal conductivity. Furthermore, we predict the thermal conductivity of a three-phase composite material, as these engineered bamboo products can be described, using micromechanical analysis. This provides important insights on density-thermal conductivity relations in bamboo, and for the first time, enables us to determine the fundamental thermal properties of the bamboo cell wall. Moreover, the density-conductivity relations in bamboo and engineered bamboo products are compared to wood and other engineered wood products. We find that bamboo composites present specific characteristics, for example lower conductivities-particularly at high density-than equivalent timber products. These characteristics are potentially of great interest for low-energy building design. This manuscript fills a gap in existing knowledge on the thermal transport properties of engineered bamboo products, which is critical for both material development and building design.

Chemical composition of processed bamboo for structural applications

“…This suggests that untreated bamboo would have the highest porosity content (Eq. 2 ) at 62.5%, with the porosity content of bleached bamboo at 57.1% and of caramelised bamboo at 54.3% where cell wall density is assumed to be 1500 kg/m 3 (Shah et al 2016 ).…”

The Optimal Tuning, within Carbon Limits, of Thermal Mass in Naturally Ventilated Buildings

“…• The graphs reveal many situations in which l 5 cm, suggesting that thin-shell structures of minimum weight [104][105][106][107][108][109][110] may also be optimized for thermal mass and natural ventilation. • While not analyzed here, the thermal properties of earthen materials [115] and high-density bamboo composites [116] suggest that these materials are promising candidates, too.…”

Surface‐Carbonized Bamboos with Multilevel Functional Biostructures Deliver High Photothermal Water Evaporation Performance

“…[ 32 ] They can withstand high thermal gradients and avoid thermal‐stress‐related cracking. [ 33,34 ] The unique mechanical and thermal structures of bamboos also indicate their competitiveness as novel photothermal materials. [ 32,33,35–37 ] Fully carbonized bamboos [ 36 ] and plasmonic bamboos [ 37 ] have been successfully developed for solar steam generation, with solar‐thermal efficiencies of 62.3% and 71.5%, respectively.…”