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34 records – page 1 of 4.

An Analytical, Numerical and Experimental Study of Non-Metallic Mechanical Joints for Engineered Timber Constructions

https://research.thinkwood.com/en/permalink/catalogue1606
Year of Publication
2016
Topic
Connections
Mechanical Properties
Material
LVL (Laminated Veneer Lumber)
Author
Bazu, Gheorghe
Mahjourian Namari, Siavash
Wehsener, Jörg
Hartig, Jens
Haller, Peer
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
LVL (Laminated Veneer Lumber)
Topic
Connections
Mechanical Properties
Keywords
GFRP
Densified Veneer Wood
Plates
Dowels
Load Bearing Behaviour
Analytical Model
Numerical Model
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 2059-2068
Summary
Timber structures are strongly depending on the design of connections, which are mostly constructed from steel components. However, these joints have a number of limitations such as the tendency to be heavy, proneness to corrosion and often poor aesthetic appearances. Therefore, this study aims to replace metallic joints by non-metallic materials. An experimental testing program was performed to investigate the use of glass fiber reinforced plastics (GFRP), densified veneer wood (DVW) and laminated veneer lumber (LVL) in the form of plates and dowels in different test configurations. Analytical and numerical models were developed to better understand the load-bearing behaviour and to perform static verifications. The models were validated based on the experimental results. The results demonstrate that the use of GFRP dowels in combination with GFRP plates can provide a robust connection system for contemporary applications.
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Connection and Performance of Two-Way CLT Plates

https://research.thinkwood.com/en/permalink/catalogue1482
Year of Publication
2018
Topic
Mechanical Properties
Connections
Material
CLT (Cross-Laminated Timber)
Application
Floors
Roofs
Author
Zhang, Chao
Lee, George
Lam, Frank
Organization
University of British Columbia
Year of Publication
2018
Country of Publication
Canada
Format
Report
Material
CLT (Cross-Laminated Timber)
Application
Floors
Roofs
Topic
Mechanical Properties
Connections
Keywords
Two-Way
Bending Test
Modulus of Elasticity
Self-Tapping Screws
Glued-In-Rod
Steel Connectors
Steel Plates
Language
English
Research Status
Complete
Summary
The two-way action of Cross Laminated Timber (CLT) is often ignored in the design of CLT due to its complexity. But in some cases, for example, large span timber floor/roof, the benefit of taking the two-way action into account may be considerable since it is often deflection controlled in the design. Furthermore CLT panels are typically limited to widths of less than 3 m. therefore, for practical applications, engaging CLT panels in two-way action as a plate in bending would require connecting two panels in the width/minor direction to take out-of-plane loading. To address this technically difficult situation, an innovative connection was developed to join the CLT panels in the minor direction to form a large continuous two-way plate. The two-way action of CLT was also quantified. Static bending test was conducted on CLT panels in the major and minor directions to measure the Modulus of Elasticity (MOE). This provided a benchmark for the following connection test, and data for the future development of computer modeling. The average apparent MOE was 9.09 GPa in the major direction and 2.37 GPa in the minor direction. Several connection techniques were considered and tested, including self-tapping wood screws, glued in steel rods, and steel connectors. One connecting system was found to be effective. For the panel configuration considered, the system was consisted of steel plates, self-tapping wood screws, and 45° screw washers. Two steel plates were placed on the tension side with sixteen screws, and one steel plates was placed on the compression side with four screws. When the screws were driven into the wood, the screws were tightly locked with the washers and steel plates, and at the same time, the wood members were pulled together by the screws. This eliminated any original gap within the connection. The connector was installed to join two CLT members in the minor direction. They were tested under bending with the same setup as above. The connected panels had an average apparent MOE of 2.37 GPa, and an average shear-free MOE of 2.44 GPa, both of which were higher than the counterpart in the full panels. The moment capacity of the connected panels was also high. The minimum moment capacity was 3.2 times the design value. Two large CLT panels were tested under concentrated loading with four corners simply supported. The deflection of nine locations within the panels was measured. This data will be used to validate the computer modeling for CLT two-way action.
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A Contribution to the Design of Ribbed Plates

https://research.thinkwood.com/en/permalink/catalogue1692
Year of Publication
2016
Topic
Design and Systems
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Author
Augustin, Manfred
Zimmer, Severin
Bogensberger, Thomas
Sleik, Tim
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Topic
Design and Systems
Mechanical Properties
Keywords
Ribbed Plates
Elastic Model
Shear Stresses
Tensile Stresses
Notches
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 4262-4271
Summary
The topic of this paper is the discussion of a proposal for the design of ribbed plates built-up with CLT (plate)- and GLT (ribs)- members. The suggested elastic model is based on the work of Abdelouahed [13] and Smith and Teng [14] for the strengthening of concrete members with FRP plates and will be applied for the mentioned loadcarrying timber elements. As a result so far it could be observed, that high peaks of shear and tensile stresses perpendicular to the interface (glue-line) occur due to the elastic consideration of the material. The model was evaluated by some pre-test which showed an acceptable correlation between the predictions of the model and a 2D-FEM analysis. It is evident, that the notches at the end of the rips must be reinforced by e.g. self-tapping screws or glued in rod to achieve effective solutions for this load carrying element. With the discussed model the shear and tensile stresses and forces resp. perpendicular to the interface can be computed.
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Development and Evaluation of Mechanical Joints for Composite Floor Elements with Cross Laminated Timber

https://research.thinkwood.com/en/permalink/catalogue208
Year of Publication
2015
Topic
Connections
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Timber-Concrete Composite
Application
Floors
Author
Jacquier, Nicolas
Organization
Luleå University of Technology
Year of Publication
2015
Country of Publication
Sweden
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Timber-Concrete Composite
Application
Floors
Topic
Connections
Mechanical Properties
Keywords
Fasteners
Metal Plate
Strength
Stiffness
Double-sided Nail Plates
Language
English
Research Status
Complete
Summary
This thesis focuses on the development of composite floor solutions where Cross Laminated Timber (CLT) panels are used as a base element. Preliminary investigations on shear connections between prefabricated concrete beams and CLT panels were performed. The focus is on investigations on glulam-CLT composite beam elements, and the mechanical shear connectors used to achieve composite action. The new shear connections system evaluated in this thesis for glulam-CLT floor elements consists of double-sided punched metal plate fasteners. In order to secure the shear connection made with double-sided nail plates and to improve the shear behaviour of the joint, a combination with inclined self-tapping screws was evaluated through a shear test programme. It was found that the double-sided punched metal plate fasteners and inclined screws can effectively be combined.
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Displacement Design Procedure for Cross Laminated Timber (CLT) Rocking Walls with Sacrificial Dampers

https://research.thinkwood.com/en/permalink/catalogue395
Year of Publication
2015
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Gu, Mengzhe
Pang, Weichiang
Schiff, Scott
Organization
Structures Congress
Publisher
American Society of Civil Engineers
Year of Publication
2015
Country of Publication
United States
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Design and Systems
Seismic
Keywords
Energy Dissipation
Ductile Behavior
U-Shaped Flexural Plates
Self-centering Mechanism
Language
English
Conference
Structures Congress 2015
Research Status
Complete
Notes
April 23–25, 2015, Portland, Oregon, USA
Summary
This paper presents the preliminary design of a rocking Cross-laminated Timber (CLT) wall using a displacement-based design procedure. The CLT wall was designed to meet three performance expectations: immediate occupancy (IO), life safety (LS), and collapse prevention (CP). Each performance expectation is defined in terms of an inter-story drift limit with a predefined non-exceedance probability at a given hazard level. U-shape flexural plates were used to connect the vertical joint between the CLT panels to obtain a ductile behavior and adequate energy dissipation during seismic motion. A design method for ensuring self-centering mechanism is also presented.
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Economic-Design Optimization of Cross Laminated Timber Plates with Ribs

https://research.thinkwood.com/en/permalink/catalogue1362
Year of Publication
2016
Topic
Cost
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Stanic, Andjelka
Hudobivnik, Blaž
Brank, Boštjan
Publisher
ScienceDirect
Year of Publication
2016
Country of Publication
Netherlands
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Cost
Mechanical Properties
Keywords
Plates
Eurocode 5
Language
English
Research Status
Complete
Series
Composite Structures
Summary
An economic-design optimization of cross-laminated timber (CLT) plate with stiffening ribs is presented. For the structural analysis, an enhanced assumed strain (EAS) solid finite element is used. It behaves well for thin plates (with no shear locking) and delivers reasonable approximations for the transverse shear stresses in layered composites. Eurocodes 5 (EC5) are followed in defining the optimization constraints, which include deflections, stresses and fundamental eigenfrequency. The gradient optimization is performed. Analytical expressions for sensitivities are obtained by an automatic differentiation tool. The result is an economic timber plate configuration that complies with the EC5 requirements. Numerical examples are presented in order to illustrate the approach.
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Effects of Arrangement of Steel Plates on Strength of Dowel-Type Cross Laminated Timber Joints with Two Slotted-In Steel Plates Subjected to Lateral Force

https://research.thinkwood.com/en/permalink/catalogue1564
Year of Publication
2016
Topic
Connections
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Sawata, Kei
Kawamura, Hirokatsu
Takanashi, Ryuya
Ohashi, Yoshinori
Sasaki, Yoshihisa
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Topic
Connections
Mechanical Properties
Keywords
Dowel-Type Joints
Steel Plates
Johansen's Yield Model
Yield Modes
Strength
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 1556-1563
Summary
Cross-laminated timber (CLT) has received particular attention as a structural material, and its material and joint strengths have been researched. This study derived a strength formula for dowel-type CLT joints with slottedin two steel plates, based on Johansen’s yield theory. When the steel plate is inserted in CLT that has five laminae, the dowel-type joints with slotted-in two steel plates have thirty-nine yield modes. This study derived the formulas for each yield mode and compared them with experimentally obtained results. The yield mode assumed by the yield theory was congruent with the failure mode of the CLT specimens after the experiments. The strength of dowel-type joints calculated based on the yield theory was close to the yield strength obtained in the experiments.
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Elastic Behavior of Cross Laminated Timber and Timber Panels with Regular Gaps: Thick-Plate Modeling and Experimental Validation

https://research.thinkwood.com/en/permalink/catalogue1341
Year of Publication
2017
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Franzoni, Lorenzo
Lebée, Arthur
Lyon, Florent
Forêt, Gilles
Publisher
ScienceDirect
Year of Publication
2017
Country of Publication
Netherlands
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Mechanical Properties
Keywords
Homogenization
Gaps
Elastic Behavior
Bending Stiffness
Thick Plates
Language
English
Research Status
Complete
Series
Engineering Structures
Summary
In the present paper, the influence of periodic gaps between lamellas of Cross Laminated Timber (CLT) on the panel’s elastic behavior is analyzed by means of a periodic homogenization scheme for thick plates having periodic geometry. Both small gaps, due to the fabrication process of not-gluing lateral lamellas, and wider gaps are investigated. The results obtained with the periodic homogenization scheme are compared to existing closed-form solutions and available experimental data. It appears that the plate bending stiffness can be well predicted with both homogenization and simplified methods, while only the homogenization approach is in agreement with the experimental in-plane and out-of-plane shear behavior. The influence of several properties of CLT lay-up on the mechanical response is pointed out as well.
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Energy Based Seismic Design of a Multi-Storey Hybrid Building: Timber-Steel Core Walls

https://research.thinkwood.com/en/permalink/catalogue1271
Year of Publication
2016
Topic
Seismic
Design and Systems
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Author
Goertz, Caleb
Organization
University of British Columbia
Year of Publication
2016
Country of Publication
Canada
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Topic
Seismic
Design and Systems
Keywords
Timber-Steel Hybrid
Core Walls
Multi-Storey
High Seismic Regions
Steel Plates
Equivalent Static Force Procedure
Nonlinear Time History Analysis
Language
English
Research Status
Complete
Summary
This thesis discusses a novel timber-steel core wall system for use in multi-storey buildings in high seismic regions. This hybrid system combines Cross Laminated Timber (CLT) panels with steel plates and connections to provide the required strength and ductility to core walled buildings. The system is first derived from first principles and validated in SAP2000. In order to assess the feasibility of the system it is implemented in the design of a 7-storey building based off an already built concrete benchmark building. The design is carried out following the equivalent static force procedure (ESFP) outlined by the National Building Code of Canada for Vancouver, BC. To evaluate the design bi-directional nonlinear time history analysis (NLTHA) is carried out on the building using a set of 10 ground motions based on a conditional mean spectrum. To improve the applicability of the hybrid system an energy based design methodology is proposed to design the timber-core walled building. The methodology is proposed as it does not rely on empirical formulas and force modification factors to determine the final design of the structure. NLTHA is carried out on the proposed methodology using 10 ground motions to evaluate the suitability of the method and the results are discussed and compared to the ESFP results.
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Evaluation of the Structural Behaviour of Beam-Beam Connection Systems Using Compressed Wood Dowels and Plates

https://research.thinkwood.com/en/permalink/catalogue2050
Year of Publication
2018
Topic
Connections
Material
Glulam (Glue-Laminated Timber)
Application
Beams

34 records – page 1 of 4.