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formance across the adhesive types was found to be consistent between
specimen sets.
34-7-4 J Kangas, A Kevarinmäki
Quality control of connections based on in V-shape glued-in steel rods
Introduction
Design method of connections based on glued-in rods forming V-shape
has been presented in CIB. It is based on large test series of high capacity
connections with numerous rods during the past ten years. In Finland
standardised steel elements for these connections and a special apparatus
for manufacturing the connections have been developed. They were also
used in making the connections for the latest test series. The quality control
method is developed for the manufacturer who is specialised in fabricating
structures with these apparatuses. The purpose is to prevent or at
least to minimise the effect of the possible production errors. Already thirty
years glued in screws have been used in Finland in the heel connections
of glulam columns. They have their own quality control method.
This paper presents a method for the quality control of manufacturing
the V-connections.
34-7-6 A Bernasconi
Behaviour of axially loaded glued-in rods – Requirements and resistance,
especially for spruce timber perpendicular to the grain direction
Introduction
Glued-in rods allow the introduction of high forces in timber elements.
The bond between rods and timber is given by an adequate bond system
with sufficient ultimate strength and rigidity, in order to assure a strong
bond between the rod material and the timber. To describe the behaviour
of glued-in rods and to give a basis for the design, it is necessary to determine
the influence of different parameters on the strength of the bond system.
Under normal timber building conditions the gluing of steel is complex.
The profile of the steel rods - in form of threads or ribs - is an interesting
possibility to avoid the gluing of steel. The mechanical connection given
by the ribs assure the load transfer from the steel to the glue-line. In the
case of a sufficient resistance of the glue system a shear failure of the timber
adjacent to the hole occurs. That way the best capacity of the bond is
reached.
The shear strength of the timber depends on several parameters. The
description of the influence of the different influence factors and the description
of the stress distribution in the bond line is the starting point for
the experimental analysis of the timber strength with use of pull-out tests.
Following the analysis of the results from several experimental pull-out
tests on glued-in rods perpendicular to the grain direction with spruce timber,
it shows that the strength depends principally on the hole diameter.
The other factors of influence have a smaller influence on the strength.
These results allow to give a proposal for the design of glued-in rods perpendicular
to the grain with spruce timber.
34-7-8 C Bengtson, C-J Johanson
Glued-in rods for timber structures
Summary and introduction
Glued-in rods have been used during a number of years in several of the
European countries which are active in timber engineering. They are economically,
architecturally and industrially attractive means of transferring
forces within a structure and of providing local reinforcement to critical
zones of timber members. They also provide an important technology for
the repair and upgrading of historically important timber structures which
exist throughout Europe. Notwithstanding their importance, internationally
accepted design rules for glued-in rods do not exist. This paper presents
the main findings within the EU-project "Glued-in rods for timber structures"
(GIROD). The project started in February 1998 and ended in March
2001. The paper is based on summaries written by the different partners in
the project: Swedish National Testing and Research Institute (SP, coordinator),
University of Lund (Sweden), TRADA Technology Ltd (UK),
University of Karlsruhe (Germany) and FMPA in Stuttgart (Germany).
Additionally, glulam- and adhesive producers from Sweden and Germany
participated in the project. The main structure of the project is given below:
CIB-W18 Timber Structures – A review of meeting 1-43 4 CONNECTIONS page 4.52