Page 67 - ROHANA_Journal_No_11-2019-ok

Research Journal of the University of Ruhuna, Sri Lanka- Rohana 11, 2019

grade compressive stress. Table 3 summarizes compression perpendicular to grain
grade stresses.

45 Clear Timber
Specimen
40
COMPRESSIVE STRENGTH PARALLEL TO GRAIN /(N/mm²) 30 Timber
Finger Jointed
35
Specimen
25
20
15
10
5
0

TIMBER SPECIES

Source: Author compiled

Figure 10: Comparison of the average compressive strength parallel to grain of
different timber species

Table 3. Compression perpendicular to grain test results

Compressive strength perpendicular to Grade stresses
grain
Species Finger Strength Finger
Clear Clear
2
(N/mm ) jointed reduction (N/mm ) jointed
2
2
2
(N/mm ) % (N/mm )
Teak 8.53 10.08 -18.13 4.88 5.76
Satin 15.51 17.16 -10.66 8.86 9.8
Mahogany 7.85 8.13 -3.66 4.48 4.65
Jak 13.43 11.03 17.90 7.67 6.3
Kumbuk 7.71 8.28 -7.31 4.41 4.73
Grandis 5.14 5.38 -4.72 2.94 3.07
Pine 6.06 7.72 -27.39 3.46 4.41
Source: Author compiled

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