Franke, Steffen; Franke, Bettina; Schiere, Marcus; Bonifacio, Sébastien; Müller, Andreas (12 May 2022). Monitoring systems for quality assurance of timber bridges In: 4th International Conference on Timber Bridges (ICTB 2021PLUS): Conference Proceedings (pp. 1-10). Berner Fachhochschule 10.24451/w5yg-j871
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Franke Franke Schiere Bonifacio Müller 2022 ICTB2021Plus - Monitoring systems.pdf - Accepted Version Available under License Publisher holds Copyright. Download (1MB) | Preview |
Wood properly protected and controlled is very powerful and durable. Continuous monitoring of wood moisture content is a suitable early warning system. The importance of wood moisture in relation to possible damage in timber construction is shown by the study of [1], where 50 % of all investigated objects show damage or failure due to wood moisture changes or low and high wood moisture contents. Another study by [2] shows that 30% of these objects are damaged due to seasonal or climate-induced wood moisture changes. Since the distribution of wood moisture is often not constant across the cross-section, internal stresses perpendicular to the grain (moisture-induced stresses, MIS) arise due to the anisotropic moisture-strain behaviour. These stresses can easily exceed the characteristic tensile strength perpendicular to the grain and lead to crack development, [3]. In curved glulam beams, these stresses can also lead directly to the total loss of load-bearing capacity, as shown in [4] or [5].