Functionalised adhesive bondlines as sensor in engineered wood

The building industry is one of the most polluting with 40% of annual global CO2 emissions. (IEA,2022)

In order to reduce these emissions and respond to environmental challenges, wood is becoming a preferred building material because of its positive environmental impact compared to the high carbon footprint materials currently used in construction.

Nevertheless, timber structures may be subjected to performance losses for cases of undetected moisture ingress. Therefore, there would be a need for an early detection of excessive moisture in engineered wood products to ensure their durability.

Nowadays, such a monitoring is frequently omitted or only done locally performed while it may alter the integrity of the structures.

This doctoral thesis aims to tackle this challenge, which is part of the project "i³sense – Intelligent, integrated and impregnated cellulose based sensors for reliable bio-based structures” (Figure 1), a COMET Module funded by FFG. [1]

The approach of this dissertation is to turn the engineered wood products into an embedded sensor system by functionalizing the adhesive bondline with conductive fillers. This project aims to understand how electrical properties of wooden composites are affected by hygrothermal and mechanical stresses, and how this knowledge can be used to monitor the structural integrity in situ.

^{Figure 1: Graphical summary of the Module i3Sense - project proposal}

[1] https://www.ffg.at/comet