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30-7-1 K Komatsu, A Koizumi, T Sasaki, J L Jensen, Y Iijima
Flexural behavior of GLT beams end-jointed by glued-in hardwood
dowels
Abstract
Recently in Japan, hardwood dowel has been getting a new reputation as
an alternative jointing device for engineered timber joints because it can
be harmonized with timber structural members more gently than such
jointing system as steel drift-pins or bolts with steel gusset plates. As the
first step of utilizing this natural jointing device for engineered timber
structures, a series of pull-out shear strength test has been done on single
dowel joints glued with polyurethane adhesive.
End-jointed GLT beams using adhesive and hardwood dowels.
This paper follows after the first step mentioned above, and gives preliminary
results on the theoretical prediction of flexural behaviour of GLT
beams which were end jointed using several hardwood dowels with polyurethane
adhesive as shown in the figure.
32-7-12 H J Blass, B Laskewitz
Effect of spacing and edge distance on the axial strength of glued-in
rods
Introduction
Glued-in rods have been used for several years in timber structures to
transfer high forces from one structural element to another. In addition
they are used as a reinforcement perpendicular to the grain in timber
members. However, generally accepted design rules for glued-in rods are
still missing.
Since 1998, the European Union supports the research project GIROD,
in which design rules for glued-in rods will be drafted for inclusion in Eurocode
5. This research project is divided into several working packages
carried out by different European partners. The University of Karlsruhe is
responsible for working package 3 where the minimum spacing and the
minimum end and edge distances of glued-in rods are determined.
This paper presents test results with axially loaded rods glued in parallel
to the grain in oversized holes in glued laminated timber members and
proposes minimum rod-to-edge distances and rod spacing for timber
members.
Conclusion
When using glued-in rods in timber structures it is suggested to use spacings
of 5 times and edge distances of 2.5 times the rod diameter. Otherwise,
a decrease in load-carrying capacity should be taken into account. It
is recommended not to use edge distances below two times the rod diameter
because of inevitable inaccuracies when drilling the holes for glued-in
rods.
32-7-13 C J Mettem, R J Bainbridge, K Harvey, M P Ansell, J G Broughton,
A R Hutchinson
Evaluation of material combinations for bonded-in rods to achieve improved
timber connections
Abstract
Well designed and executed adhesive bonded structural connections can
be extremely efficient and may possess many desirable attributes in terms
of manufacture, performance, aesthetics and cost. The use of bonded-in
rods is an important feature of many of the methods for achieving connections
using adhesives.
Bonded-in rods are now being used in several European countries, but
the performance requirements and the design rules differ, which is a seri-
CIB-W18 Timber Structures – A review of meeting 1-43 4 CONNECTIONS page 4.49