Dowel-laminated timber (DLT) elements consist of lamellae arranged side-by-side that are connected with beech dowels. Due to the glue-free DLT element layup, joints and shear walls potentially suffer from considerable reduction of stiffness and load carrying capacity as metal fasteners inserted perpendicular to the element plane may be placed in gaps between the single lamellae. Tests on typical joints showed that, depending on the fastener diameter, the remaining load carrying capacity of joints in DLT in comparison to joints in solid wood may be only 25%. Tests on DLT shear walls with different sheeting proved that the use of DLT structures as shear walls is only possible if at least one-sided sheeting is used. Cyclic tests on DLT shear walls demonstrated that the DLT construction typology has energy dissipation properties similar to traditional timber frame construction. Analogously, preliminary behaviour factors for DLT buildings evaluated with numerical models were also similar to those for timber frame buildings.
The present work aims to define horizontal joint dimension tolerances for newly proposed prefabricated façade systems for applications in tall cross laminated timber (CLT) buildings based on the compression perpendicular to grain characteristics of the component. This requires a thorough understanding of structural settlement under vertical loads which can vary at each floor height. An experimental program has been carried out with reference to the case of a platform frame building construction, where major perpendicular to grain compression of the floor can occur under high loads. Five-layer CLT specimens have been tested under compression via the application of a line load with steel plate as well as actual CLT wall specimens. Strengthening contribution using full threaded self-tapping wood screws has also been investigated. Results of deformation characteristics have been validated through a non-linear finite element analysis and further elaborated in order to outline implications in the design of a prefabricated façade.
Cross laminated timber (CLT) members are especially suited for in-plane loads due to their high shear strength and stiffness. However, available connection techniques show limited load-carrying capacities and stiffness values in comparison to the shear capacity of CLT. To use the potential of CLT under in-plane loading, new connection techniques, so called contact joints, with increased stiffness and load-carrying capacities were developed. 10 different types of these contact joints, varying geometry and connector material, were studied. The developed contact joints can substitute traditional connection techniques.
We propose the high productivity timber joint system based on combining the medium-sized wood lumber as assembly large cross-section member. In general, the wood frame structures are required high ductility performance. In this study, the surfaces of the member joints are covered with fiber reinforced plastics (FRP) to improve the mechanical properties to achieve high ductility wood joints. It will be construction of outstanding architectural space to earthquake resistance by these wood frame structure. The purpose of this study is to investigate the seismic performance of joint and to propose the assembling large cross-section timber joint system by high ductility wood frame structure
The purpose of this study is to develop a high strength leg joint for shear wall made of small size cross laminated timber panel in a simple system. The joint of CLT in which steel plate was inserted in the central slit and fixed by high strength bolt at inside of short steel pipes was proposed. In order to grasp the failure mode and strength of CLT member, material tests on embedment and shear were carried out using small CLT blocks. The test results indicated that there is few reinforce effect by cross bonding of each lamina. It was concluded that the precise estimation of the strength of CLT member is important in order to develop the joint proposed in this paper.
Compression tests were conducted on the glulam members under different eccentricities, including three cases of 0mm,50mm and 100mm respectively, to study the mechanical performance of the new assemblage joints in reticulated timber shells. The bending stiffness and bending capacity of joints were evaluated, at the same time, the influence of failure mode and the changes...
International Association for Bridge and Structural Engineering Conference
September 23-25, 2015, Geneva, Switzerland
This paper deals with a contemporary integrated and sustainable construction technology for new residential buildings. Specifically, this research aims at developing innovative steel-timber hybrid structures which allow a rapid assembly of the individual prefabricated components, minimizing the construction times and limiting the costs of the work. The numerical analyses performed on a multi-storey building for social housing will be presented and discussed. The in-plane behaviour of the floors and shear walls will be analysed, considering in particular the types and arrangement of the different timber- and steel-timber joints. The connections to be used among the construction elements will be selected in order to develop a sufficient stiffness, ductility and bearing capacity according to the design criteria for seismic-resistant structures. These connections allow to enhance the on-site assembly operations, therefore working effectively also under harsh climatic conditions.