The characterization of the behaviour of connectors used in Cross-laminated Timber (CLT) structures is an important aspect that needs to be considered in their seismic design. In this paper, the data from shear and axial tests conducted on connectors have been used to define their force-displacement curves under cyclic loads using the SAWS model in OpenSees. The component curves were then incorporated into the corresponding wall models and the results were compared with their experimental counterparts, in order to determine the validity of the finite element model. Thereby, the non-linear behaviour was restricted to the connectors while the walls themselves were composed of linear orthotropic shell elements. The models were found to provide a good estimate of the initial stiffness and maximum load capacity of the wall specimens. The effects of vertical loading and the presence of openings were determined based on analyses run on the calibrated model.
Approximately 60% of all joints in solid timber structures assembled with Cross Laminated Timber (CLT) are realised with screws. Although, the behaviour of axially loaded self-tapping single screws is already well known, only minor experiences are available regarding the behaviour of screwed wall joints. Furthermore, since seismic resistance of CLT structures depends to a great amount on the connections’ ability to dissipate energy, it is important to extend the knowledge on their behaviour more thoroughly. This paper gives a brief overview of the results obtained from experimental monotonic and cyclic tests that were carried out not only on screwed CLT single joints, but also on wall tests with screwed joints. Additionally, the question on modelling the behaviour of a screwed wall joint based on the behaviour of a single screw will be discussed within the present contribution as well. Aforementioned tests are part of an extensive ongoing study investigated at the Graz University of Technology, Institute of Timber Engineering and Wood Technology (TU Graz) and at the competence centre holz.bau forschungs gmbh (hbf).
This document reports the outcome of the seismic test on the TUGraz building, the fourth in a
total of four buildings included in the TIMBER BUILDINGS Project. This building is a cross
laminated system (CTL). The goal of the tests was to assess the seismic performance of the
building, panel elements and steel connectors, defined in terms of relative displacements and
hold-down forces. This report presents the results of the experimental tests carried out in the LNEC 3D shaking table on a cross laminated system (CTL). The tests were carried out on February 20 and 21, 2013 on a three storey real scale building.