Proceedings e report - Firenze University Press

WOOD SCIENCE FOR CONSERVATION OF CULTURAL HERITAGE
complicating reconstructions. Acoustic reconstructions should be based on standing trees above the
buttresses.
Resistance and velocity values are not easy to link since they weren’t taken at exactly the same spot
but 5 to 10 cm one below the other. The presence of buttresses also influences results but there is no
general trend visible in velocity or resistance measurements. Buttresses sound quite hollow but can
cause reaction wood once they join the main stem, creating additional density variations. Analysis of
density (buttresses, wood cores and stem disks) is recommended to find the missing link between
resistance and velocity measurements.
(a) (b)
Fig. 3 – Two-dimensional reconstruction of two stem disks. From top to bottom, the stem surface,
the resistance (%) and acoustic reconstruction with travel times (10 -5 s) is shown.
(a) Stem disk 3.1 with rot and a cavity in the central part of the stem
(b) Stem disk 7.1 with discoloured wood or limba noir
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