00694 Pouyan Zarnani - Timber Design Society

Predicted Average Strength [kN]
Predicted Average Strength [kN]
Predicted Average Strength [kN]
(a)
(b)
(c)
1800
1600
1400
1200
1000
800
600
400
1600
1400
1200
1000
800
600
400
200
1600
1400
1200
1000
800
New Analytical M.
r² = 0.87
MAE=+0.9%
STDEV=20.3%
200
New Analytical M.
0
0 200 400 600 800 1000 1200 1400 1600 1800
Observed Average Test Strength [kN]
Stahl's Method
r² = 0.78
MAE=+2.1%
STDEV=29.4%
0
0 200 400 600 800 1000 1200 1400 1600
Observed Average Test Strength [kN]
EC5
r² = 0.67
MAE=+2.8%
STDEV=28.7%
Stahl's Method
600
O86-09 Code
r² = 0.78
400
MAE=-23.2%
STDEV=18.5%
200
O86-09 Code
0
EC5
0 200 400 600 800 1000 1200 1400 1600
Observed Average Test Strength [kN]
Figure 13: Comparison of analyses and test data
(current and literature data) in brittle/mixed failure modes;
(a) new analytical method, (b) Stahl’s method, (c) O86
code and EC5
6 CONCLUSONS
A close form stiffness-based analytical model to
determine the wood resistance of riveted connections in
timber products is proposed. It takes into account the
stiffness and strength of the failure planes subjected to
non-uniform shear and tension stresses in wood. Results
of current tests and data available from literature confirm
that this closed form analytical method can be used as
design provision with more precise predictions for
timber riveted connections. Based on the proposed
design model, an efficient connection design can be
made by decreasing the difference between the capacity
of the wood and the rivets. The proposed method can be
extended to other small dowel type fastener; e.g. nails
and screws for connection design improvement and
failure modes prediction.
ACKNOWLEDGEMENTS
The authors wish to thank the Structural Timber
Innovation Company (STIC) for funding this research
work.
REFERENCES
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