Fracture Mechanics Models for Brittle Failure of Bottom Rails due to Uplift in Timber Frame Shear Walls
Table 2
Results from testing of specimens with the pith oriented upwards (PU). 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
12.6
12.6
—
—
1
—
—
—
—
2
11.3
11.3
—
—
2
25.0
25.0
—
—
3
17.0
12.9
21.0
—
3
30.8
30.8
—
—
4
24.1
24.3
23.8
—
4
—
—
—
—
2
1
21.5
—
21.5
—
—
2
21.2
—
21.2
—
3
28.9
30.6
27.1
—
3
1
19.9
—
19.9
—
—
2
27.1
—
27.1
—
(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)
17.0
17.0
—
—
1
1
9.49
9.49
—
—
1
17.6
17.6
—
—
2
10.6
10.6
—
—
2
19.5
19.5
—
—
3
17.1
16.8
—
18.7
3
34.0
33.4
35.8
—
4
19.4
19.4
18.1
20.1
4
39.5
—
37.8 (39.5)
44.5
2
1
12.2
12.2
—
—
—
2
16.9
16.6
17.5
—
3
22.6
23.2
22.2
—
3
1
18.6
17.9
18.6
18.9
—
2
21.3
—
21.4
20.8
Series 1 of study A had a nail distance of 50 mm instead of 25 mm as the other two series of study A. Set with boundary conditions as in study A. For two specimens of this set, it was difficult to establish if the failure mode was mode 2 or 3. The results without parenthesis refer to the case of six results of failure mode 2 and two results of failure mode 3, while the results in parenthesis refer to the case of eight results of failure mode 2.
