Investigating the effects of moisture ingress on the performance and service life of Australian mass timber panels-characterization outcomes

Abstract

Composite timber systems made of timber and massive wood products used in construction are susceptible to moisture fluctuations during transport, construction, and post-construction. The wetting dynamics, both ingress and egress, of Australian timber species and mass panels exposed to Australian climate conditions have not been extensively explored. Understanding moisture movement in timber is crucial for predicting the design life of timber products and developing decay modelling protocols. An experimental testing has been conducted in detail to comprehend water movement and moisture gradients in massive wood-based composites. The testing results presented in this paper include the density, porosity, gas, and liquid permeability of three Australian timber species (radiata pine, southern pine and shining gum). The experiments have been designed to explore the hygroscopic properties of timber species in different directions, including face, edge and end and of CLT (2P and 3P) and LVL sections. The porosity values for the three tested species were 56% ± 5, 57% ± 3 and 42% ± 8 for radiata pine, southern pine and shining gum respectively. The experimental results presented in this paper showed that CLT samples made from radiata pine with edge gap (3P) had higher porosity and permeability values than solid radiata sample sections. The CLT 2P sections had lower porosity values than the solid radiata pine samples. The porosity values determined for LVL (made from pine) samples (51% ± 3) were slightly lower than southern pine samples tested. The outcomes of this project will facilitate the prediction of product response to moisture and enable the development of maintenance protocols and remedial solutions for the industry to minimize the potential impacts of moisture penetration in mass timber products in the future. © 2023 13th World Conference on Timber Engineering,