2 METHODS AND SOLUTIONS
2.1 Visual assessment
Visual assessment is non-destructive method used to determine the quality or locate defects and
failures of the element. On the beams attention is paid primarily to their placing in the ends, often
due to bad implementation attacked by decay. Other aspects are presence of holes, indicate the
potential infestation of the wood-destroying insects, drying cracks, rot away or fallen out knots and
other factors that affect the quality of the investigated element [4].
2.2 Drilling resistence measurement
The drilling resistance method belongs to semi destructive methods and is suitable for
identification of the internal damage of wood, such as created tunnels, cracks, decay and other
internal changes in the structure of wood.
The healthy timber shows significantly higher values of drilling resistance (higher density profile)
than the measured values for the damaged wood.
Measurements were performed using the apparatus Resistograph Resi PD 200 (see Fig. 4).
Figure 4. Resistograph Resi PD 200
3 RESULTS
Most of the elements of the assessed truss structure in the castle (vertical, horizontal and oblique)
appear to be infested (old-house borer), whether locally or over the entire length.
The wood response to tapping for most of elements is hollow. In the vicinity of the elements is
visible wooden powder (see Fig. 5).
Figure 5. Infested timber element – wood destroying insect
