The results of the drilling resistance measurement of the damaged wall plate area has an almost
zero resistance of timber (Figure 13) – it is the total destruction of the wood element, which
confirms results of the visual inspection.
Figure 13. Drilling resistance – element in the area of water leaking
4 CONCLUSIONS
The visual assessment of elements is very quick and simple method to obtain basic information
about theelement under consideration - existenceof insect holesandwoodenpowder demonstrates
wood-destroying insect infestation, hollow element response to tapping and fallen off
timber demonstrates decay infestation.
In structures where cannot be used destructive methods it is a suitable drilling resistance method,
enabling easy and rapid determination of the actual extent of the infestation and of the state of
wood mass inside the cross-sections of the assessed element.
Based on the results of the visual assessment and drilling resistance method was due to a large
extent of the wood-destroying insects and decay infestation of the roof truss, and the condition of
the roof structure recommended the total replacement truss structure.
ACKNOWLEDGEMENT
This outcome has been achieved with funds of Conceptual development of science, research and
innovation assigned to VŠB – Technical University of Ostrava by Ministry of Education Youth and
Sports of the Czech Republic.
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Nykanen, H. and Koricheva, J. 2004. Damage-induced changes in woody plants and their
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Gadi VP Reddy. Fettkoher, R., Noldt, U., Dettner, K., Enhancement of attraction and trap
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