Table 2 Mean strength values (MPa) and their standard deviation % (SD) for heat-treated and untreated beech and birch by quasi-static tests (the first number refers to the treatment temperature and the second number refers to the duration time in minutes).

From: Characterisation of thermally treated beech and birch by means of quasi-static tests and ultrasonic waves

Beech

Ref

Air

Nitrogen

150–10

200–10

250–10

150–30

200–30

250–30

150–10

200–10

250–10

150–30

200–30

250–30

fcL

80.64

75.27

79.00

76.67

85.48

93.90

58.98

90.42

92.05

78.29

86.37

93.73

32.51

SD

7.6

6.1

9.7

16.2

6.1

7.9

13.9

8.6

3.7

15.3

6.8

10.0

28.4

fcR

22.64

15.96

17.68

14.11

16.97

17.13

 

17.12

18.28

13.77

16.98

18.90

8.18

SD

0.5

0.4

0.5

0.7

0.2

0.8

 

0.5

0.5

2.7

1.7

0.4

2.5

ftL

160.58

196.99

169.1

87.40

192.04

139.30

47.89

      

SD

23.0

12.8

10.9

8.0

28.5

9.1

9.4

      

τLR

17.94

22.72

22.12

14.12

23.89

21.98

3.63

22.56

27.32

 

25.30

18.4

 

SD

1.9

1.6

1.7

1.4

2.9

1.6

1.8

2

3

 

2.7

2.4

 

Birch

 fcL

61.12

58.69

83.51

77.73

71.79

74.21

61.28

63.59

74.99

70.96

73.16

77.36

62.32

 SD

1.1

2.9

1.9

2.2

1.7

2.4

5.4

2.0

2.1

4.0

1.0

7.7

7.2

 fcR

9.57

10.61

10.8

10.5

9.8

9.9

 

10.41

10.9

8.8

11.08

11.7

4.7

 SD

0.3

0.6

0.4

1

0.4

1.6

 

0.4

0.6

2.1

0.9

0.4

1.4

 ftL

165.74

186.82

192.05

69.77

189.64

165.65

46.9

      

 SD

12.6

20.6

33.1

19.7

25.0

16.2

10.4

      

 τLR

20.17

23.79

19.55

11.47

23.69

21.64

 

23.17

23.14

 

25.05

17.08

 

 SD

1.5

1.4

1.5

1.5

1.5

1.4

 

0.4

2.7

 

2.3

2.6

 
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