Fracture Mechanics Models for Brittle Failure of Bottom Rails due to Uplift in Timber Frame Shear Walls
Table 3
Results from testing of specimens with the pith oriented downwards (PD). Failure modes are defined in Figure 2.
(a) Study A
Series
Set
Mean failure load [kN]
Set
Mean failure load [kN]
Failure mode
Failure mode
All failure modes
()
()
()
All failure modes
()
()
()
Single-sided tests
Double-sided tests
1
1
12.0
12.0
—
—
1
22.1
22.1
—
—
2
13.5
13.5
—
—
2
29.2
29.2
—
—
3
17.4
17.4
—
—
3
38.6
39.0
—
35.9
4
22.8
22.1
28.6
20.7
4
39.7
39.3
43.4
—
2
1
16.0
16.0
—
—
—
2
20.7
20.3
23.6
—
3
29.1
30.3
28.0
—
3
1
21.6
21.7
23.1
15.1
—
2
29.2
28.6
29.5
—
(b) Study B
Series
Set
Mean failure load [kN]
Set
Mean failure load [kN]
Failure mode
Failure mode
All failure modes
()
()
()
All failure modes
()
()
()
Single-sided tests
Double-sided tests
—
1-BC (A)
22.6
22.6
—
—
1
1
10.3
10.2
—
—
1
20.5
20.5
—
—
2
13.5
13.5
—
—
2
28.0
28.0
—
—
3
18.2
17.9
16.7
19.0
3
39.1
39.5
38.0
—
4
21.8
23.5
20.7
21.4
4
45.8
45.4
47.1
44.2
2
1
14.0
14.0
—
—
—
2
17.9
19.3
7.70
—
3
23.7
23.5
25.6
21.3
3
1
18.1
15.9
19.5
19.4
—
2
23.8
—
25.4
22.1
Series 1 of study A had a nail spacing of 50 mm while the other two series of study A had a nail spacing of 25 mm (except for one specimen in series 3 where the spacing by mistake was 50 mm). This specimen had by mistake a nail spacing of 50 mm instead of 25 mm, which is the reason for the ductile failure. Set with boundary conditions as in study A. Exceptionally low failure load, cause unknown.
