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7 records – page 1 of 1.

Experimental Campaign for the Mechanical Characterization of Connection Systems in the Seismic Design of Timber Buildings

https://research.thinkwood.com/en/permalink/catalogue1511
Year of Publication
2016
Topic
Connections
Mechanical Properties
Seismic
Material
CLT (Cross-Laminated Timber)
Light Frame (Lumber+Panels)
Application
Wood Building Systems
Author
Casagrande, Daniele
Polastri, Andrea
Sartori, Tiziano
Loss, Cristiano
Chiodega, Manuela
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Light Frame (Lumber+Panels)
Application
Wood Building Systems
Topic
Connections
Mechanical Properties
Seismic
Keywords
Capacity
Stiffness
Ductility
Cyclic Loads
Monotonic Loads
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 353-361
Summary
The seismic behaviour of timber buildings is strongly related to the energy dissipation capacity of connections. According to Standard, since timber is characterized by a brittle failure when subjected to tensile or bending actions, the dissipative zones shall be located in joints and connections, whereas timber members themselves shall be regarded as behaving elastically. In order to ensure the global structural ductility, connections and joints shall be able to deform plastically at the associated ductility level without a significant reduction of their resistance under cyclic loads. The paper deals with an experimental campaign for the mechanical characterization of timber connection systems, commonly adopted in Europe, in the seismic design of timber buildings. The main objective was to find out the capacity, the stiffness and the ductility of the tested connections and to investigate their loss of capacity under cyclic loads. The obtained results were analysed in order to understand if the current provisions, reported in Standard for the different typology of traditional connectors, can be adopted in case of connection systems used for seismic purposes, such as hold-down or angle brackets. Their interaction with other structural parts was then investigated testing six fullscale timber walls, subjected to monotonic and cyclic loads. The tests were carried out at the Laboratory of Materials and Structural Testing of the Trento University (Italy).
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Finite Element Modelling of the Cyclic Behaviour of CLT Connectors and Walls

https://research.thinkwood.com/en/permalink/catalogue1653
Year of Publication
2016
Topic
Mechanical Properties
Seismic
Connections
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Aranha, Chrysl
Branco, Jorge
Lourenço, Paulo
Flatscher, Georg
Schickhofer, Gerhard
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Mechanical Properties
Seismic
Connections
Keywords
Shear Tests
Axial Tests
Cyclic Loads
Force-Displacement Curves
Numerical Model
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 3533-3540
Summary
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.
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Heavy Laminated Timber Frames with Rigid Three-Dimensional Beam-To-Column Connections

https://research.thinkwood.com/en/permalink/catalogue499
Year of Publication
2014
Topic
Connections
Seismic
Material
Solid-sawn Heavy Timber
Application
Beams
Author
Kasal, Bohumil
Guindos, Pablo
Polocoser, Tiberiu
Heiduschke, Andreas
Urushadze, Shota
Pospisil, Stanislav
Publisher
American Society of Civil Engineers
Year of Publication
2014
Country of Publication
United States
Format
Journal Article
Material
Solid-sawn Heavy Timber
Application
Beams
Topic
Connections
Seismic
Keywords
Full Scale
Self-Tapping Screws
Cyclic Loads
Beam-to-Column
Language
English
Research Status
Complete
Series
Journal of Performance of Constructed Facilities
Summary
This article presents the seismic performance of a timber frame with three-dimensional (3D) rigid connections. The connections were made with self-tapping screws and hardwood blocks were used to support the beams. The frame was designed to resist high seismic excitations with the goal of controlling the drift. The moment-rotation characteristics of the connections were measured in the laboratory by applying static cyclic loads. The frame made of laminated wood beams and columns, and cross-laminated lumber deck, was subjected to seismic, white noise, snapback, and sinusoidal sweep excitations. The synthetic seismic excitation was designed to contain a considerable amount of energy close to the frame’s first natural frequency. The structure showed no significant damage up to a peak ground acceleration of 1.25g. Failure of the frame occurred due to shearing of the columns with a peak ground acceleration of 1.5g. The designed structure fulfilled with current serviceability limits up to 0.8g.
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Highly Energy Dissipative and Ductile Timber-Glass Hybrid Element

https://research.thinkwood.com/en/permalink/catalogue1744
Year of Publication
2016
Topic
Mechanical Properties
Seismic
Material
CLT (Cross-Laminated Timber)
Timber-Glass Composite
Application
Hybrid Building Systems
Author
Rajcic, Vlatka
Žarnic, Roko
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Timber-Glass Composite
Application
Hybrid Building Systems
Topic
Mechanical Properties
Seismic
Keywords
Glued-In Rods
Ductility
Energy Dissipation
Vertical Loads
Cyclic Loads
Horizontal Loads
Racking Test
Stiffness
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 4930-4937
Summary
CLT frames infilled with load-bearing glass sheets represent an innovative, hybrid structural element that can serve as load-bearing panel carrying load in both vertical and lateral direction. It can be used as a part of the prefabricated timber house or as a strengthening structural element in an existing timber building or the supporting...
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Response of CLT Shear Walls Under Cyclic Loads

https://research.thinkwood.com/en/permalink/catalogue1669
Year of Publication
2016
Topic
Mechanical Properties
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Author
MÁLAGA-CHUQUITAYPE, Christian
Skinner, Jonathan
Dowdall, Alan
Kernohan, Juliet
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Topic
Mechanical Properties
Seismic
Keywords
Cyclic Loads
Full Scale
Stiffness
Strength
Energy Dissipation
Ductility
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 3821-3827
Summary
This paper presents an experimental study into the lateral response of cross-laminated-timber (CLT) shear walls under cyclic loads with particular attention to the distribution of forces between the panel-to-floor connections. Six tests on full-scale specimens of different geometric characteristics and connection configurations are presented. The test set-up and wall configurations are described and a detailed account of the experimental results and observations is presented. The paper examines key response features including stiffness, strength, energy dissipation and ductility. Especial attention is given to an accurate measurement of the load sharing between different brackets and its evolution throughout the cyclic action. The results reported offer valuable information on the lateral forcedisplacement response of CLT walls and the applicability of widely employed design assumptions.
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Study of the Seismic and Dynamic Behavior of Glued Rod Assemblies

https://research.thinkwood.com/en/permalink/catalogue2668
Topic
Mechanical Properties
Seismic
Connections
Application
Frames
Organization
Université Laval
Country of Publication
Canada
Application
Frames
Topic
Mechanical Properties
Seismic
Connections
Keywords
Energy Dissipation
Cyclic Loads
Glued-In-Rod
Beam-Column Connection
Research Status
In Progress
Notes
Project contact is Jean Proulx at Université Laval
Summary
The main objective of the research project is to assess the behavior of bonded rod assemblies under dynamic stresses. These wood / wood connections are used in solid wood frames and allow, among other things, to transfer the moment in beam-column connections. Their ability to dissipate energy under seismic loading will be evaluated by cyclic laboratory tests by varying the sections and configurations of the assemblies. The whole structure must be able to dissipate energy under dynamic loadings (earthquakes, wind) and the demand for ductility in the assemblies is considerable in rigid frame structures. This project will make it possible to characterize the behavior of timber / timber assemblies in glued rods under cyclic loads. The results obtained can be used by the partner for the seismic design of solid wood structures using these connections. Optimization and a better understanding of the dynamic behavior of these assemblies will also increase the safety of solid wood structures, and promote their acceptance in this developing market.
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Thin Topping Timber-Concrete Composite Floors

https://research.thinkwood.com/en/permalink/catalogue902
Year of Publication
2014
Topic
Design and Systems
Mechanical Properties
Material
Timber-Concrete Composite
Application
Floors
Author
Skinner, Jonathan
Organization
University of Bath
Year of Publication
2014
Country of Publication
United Kingdom
Format
Thesis
Material
Timber-Concrete Composite
Application
Floors
Topic
Design and Systems
Mechanical Properties
Keywords
Stiffness
Vibration Response
Topping Thickness
Screws
shear connectors
Static Loads
Cyclic Loads
Short-term
Bending Tests
Language
English
Research Status
Complete
Summary
A timber-concrete composite (TCC) combines timber and concrete, utilising the complementary properties of each material. The composite is designed in such a way that the timber resists combined tension and bending, whilst the concrete resists combined compression and bending. This construction technique can be used either in new build construction, or in refurbishment, for upgrading existing timber structures. Its use is most prolific in continental Europe, Australasia, and the United States of America but has yet to be widely used in the United Kingdom. To date, the topping upgrades used have been 40mm thick or greater. Depending on the choice of shear connection, this can lead to a four-fold increase in strength and stiffness of the floor. However, in many practical refurbishment situations, such a large increase in stiffness is not required, therefore a thinner topping can suffice. The overarching aim of this study has been to develop a thin (20mm) topping timber-concrete composite upgrade with a view to improving the serviceability performance of existing timber floors. Particular emphasis was given to developing an understanding of how the upgrade changes the stiffness and transient vibration response of a timber floor. Initially, an analytical study was carried out to define an appropriate topping thickness. An experimental testing programme was then completed to: characterise suitable shear connectors under static and cyclic loads, assess the benefit of the upgrade to the short-term bending performance of panels and floors, and evaluate the influence of the upgrade on the transient vibration response of a floor. For refurbishing timber floors, a 20mm thick topping sufficiently increased the bending stiffness and improved the transient vibration response. The stiffness of the screw connectors was influenced by the thickness of the topping and the inclination of the screws. During the short-term bending tests, the gamma method provided a non-conservative prediction of composite bending stiffness. In the majority of cases the modal frequencies of the floors tested increased after upgrade, whilst the damping ratios decreased. The upgrade system was shown to be robust as cracking of the topping did not influence the short-term bending performance of panels. Thin topping TCC upgrades offer a practical and effective solution to building practitioners, for improving the serviceability performance of existing timber floors.
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7 records – page 1 of 1.