Proceedings e report - Firenze University Press

WOOD SCIENCE FOR CONSERVATION OF CULTURAL HERITAGE
Fig. 1. Cutting of diametral planks
Table 1: Characteristics of the sampling station (Arboretum of INRF Bainem)
Geographic Location Forest of Bainem
Description of settlement
Plot surface 10.04 ha
From a reforestation Artificial settlement
Composition Eucalyptus
Average height 15m
Average diameter 24cm
Spacing between 2 trees 2.5 to 3m
Average age 35 Years (1957 source INRF)
Current treatment Nil
Description of the station :
Topography Very low slope
Exposure South West
Altitude 165m
2.2. Methods
The samples (36 cubics of 20x20mm) were analyzed; the following physical characteristics were
measured: basic density, moisture content, shrinkage with collapse (before reconditioning); shrinkage
without collapse (after reconditioning).
Basic density was obtained by dividing the ovendry mass M0 (in kg) by the volume of the wood
saturated in water Vs (m 3 ):
Y = M0/Vs (1)
Vs was estimated from the maximum weight Mmax measured at saturation (Keylwerth)
Y= M0/Vs =1/ (Mmax / M0 -0,347) ) (2)
The moisture content (m.c.) was calculated as
H (%) = (mH-m0) 100/m0) (3)
where mH and m0 are the mass (in gram) of the specimen before and after oven drying, respectively.
The shrinkage was measured for every cube, according to three orthotropic directions: axial (L), radial
(R) and tangential (T), between successive states:
• Saturated state: immersion of samples in the water
• Air-dry condition, corresponding to 12% m.c.: carried out by drying the samples in a climatic
chamber conditioned to 72% R.H. (dry temperature =50°C; wet temperature =44°C) during 48
hours.
• Anhydrous state: in the oven at l30°C±2°C, (oven dry base).
The analysis of this shrinkage is performed from the average dimensions of 5 measurement points by
direction of shrinkage with a specific displacement indicator allowing a precision of 10μm (Fig. 2).
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