Abstract
The evaluation of damages in large-span timber structures indicates that the predominantly observed damage pattern is pronounced cracking in the lamellas of glued-laminated timber elements. A significant proportion of these cracks is attributed to the seasonal and use-related variations of the internal climate within large buildings and the associated inhomogeneous shrinkage and swelling processes in the timber elements. To evaluate the significance of these phenomena, long-term measurements of climatic conditions and timber moisture content were taken within large-span timber structures in buildings of typical construction type and use. These measurements were then used to draw conclusions on the magnitude and time necessary for adjustment of the moisture distribution to changing climatic conditions. A comparison of the results for different types of building use confirms the expected large range of possible climatic conditions in buildings with timber structures. Ranges of equilibrium moisture content representative of the type and use of building were obtained. These ranges can be used in design to condition the timber to the right value of moisture content, in this way reducing the crack formation due to moisture variations. The results of this research also support the development of suitable monitoring systems which could be applied in the form of early warning systems on the basis of climate measurements. Based on the results obtained, proposals for the practical implementation of the results are given.
Original language | English |
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Pages (from-to) | 153-165 |
Number of pages | 13 |
Journal | Journal of Civil Structural Health Monitoring |
Volume | 5 |
Issue number | 2 |
DOIs | |
State | Published - Apr 2015 |
Keywords
- Glued-laminated timber
- Indoor climate
- Moisture
- Moisture gradients
- Monitoring
- Relative humidity
- Shrinkage
- Shrinkage cracks
- Swelling
- Temperature
- Tension perpendicular to the grain stresses
- Timber moisture content
- Wood