End-grain bonding of spruce timber at low curing temperatures – effects on tensile strength and how to improve

The end-grain bonding of timber components using Timber Structures 3.0 technology (TS3) represents an emerging construction method in the field of timber engineering. For onsite applications, research is being conducted to determine how low temperatures during the curing process affect the bonding and to explore potential methods of mitigating any adverse impacts. The current research results reveal that low curing temperatures detrimentally influence the mechanical properties of the bond. Conversely, investigations into bonding with heated casting resin as a means to counteract the effects of low curing temperatures demonstrate highly beneficial outcomes. Overall, this study provides design-relevant tensile strength values, which, when coupled with suitable application strategies, enable effective bonding under low ambient temperatures. Future investigations will delve deeper into the failure mechanism (adhesion – cohesion) as it relates to curing temperature variations.