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35 records – page 1 of 4.

Fragility-based methodology for evaluating the time-dependent seismic performance of post-tensioned timber frames

https://research.thinkwood.com/en/permalink/catalogue2871
Year of Publication
2020
Topic
Seismic
Application
Frames
Author
Granello, Gabriele
Palermo, Alessandro
Pampanin, Stefano
Organization
University of Canterbury
ETH Zurich
Sapienza University of Rome
Publisher
SAGE Journals
Year of Publication
2020
Country of Publication
New Zealand
Switzerland
Format
Journal Article
Application
Frames
Topic
Seismic
Keywords
Pres-Lam
Post-Tensioned Timber
Fragility Analysis
Seismic Performance
Language
English
Research Status
Complete
Series
Earthquake Spectra
Summary
Since 2010, the construction of post-tensioned wooden buildings (Pres-Lam) has been growing rapidly worldwide. Pres-Lam technology combines unbonded post-tensioning tendons and supplemental damping devices to provide moment capacity to beam–column, wall–foundation, or column–foundation connections. In low seismic areas, designers may choose not to provide additional damping, relying only on the post-tensioning contribution. However, post-tensioning decreases over time due to creep phenomena arising in compressed timber members. As a consequence, there is a reduction of the clamping forces between the elements. This reduction affects the seismic response of Pres-Lam buildings in the case of low- and high-intensity earthquakes. Therefore, understanding and accounting for the post-tensioning losses and their uncertainty are paramount for a robust assessment of the safety of Pres-Lam constructions. So far, however, there have been no comprehensive studies which tackle the overall seismic performance of such systems in the presence of time-varying post-tension losses and the associated uncertainty. This study tackles this research gap by introducing a comprehensive seismic evaluation of Pres-Lam systems based on time-dependent fragility curves. The proposed fragility analysis is specifically designed to account systematically for time-varying post-tension losses and the related uncertainty. The method is applied to two case studies, designed, respectively, with and without supplemental damping devices. In terms of structural performance, results show that the use of additional dissipaters mitigates the effect of post-tensioning loss for earthquakes of high intensity. Conversely, performance under low-intensity earthquakes is strongly dependent on the post-tensioning value, as the reduction of stiffness due to the anticipated rocking motion activation would lead to damage to non-structural elements.
Online Access
Free
Resource Link
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Design and Construction of Prestressed Timber Buildings for Seismic Areas

https://research.thinkwood.com/en/permalink/catalogue1847
Year of Publication
2018
Topic
Design and Systems
Material
LVL (Laminated Veneer Lumber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems

NMIT Arts & Media Building - Damage Mitigation Using Post-Tensioned Timber Walls

https://research.thinkwood.com/en/permalink/catalogue1850
Year of Publication
2018
Topic
Design and Systems
Seismic
Material
LVL (Laminated Veneer Lumber)
Application
Floors
Walls
Columns
Beams
Wood Building Systems
Author
Devereux, Carl
Holden, Tony
Buchanan, Andrew
Pampanin, Stefano
Publisher
New Zealand Timber Design Society
Year of Publication
2018
Country of Publication
New Zealand
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Application
Floors
Walls
Columns
Beams
Wood Building Systems
Topic
Design and Systems
Seismic
Keywords
Earthquake
Structural
Shear
Post-Tensioning
Language
English
Research Status
Complete
Series
New Zealand Timber Design Journal
Online Access
Free
Resource Link
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Preventing Seismic Damage to Floors in Post-Tensioned Timber Frame Buildings

https://research.thinkwood.com/en/permalink/catalogue1851
Year of Publication
2018
Topic
Design and Systems
Seismic
Material
LVL (Laminated Veneer Lumber)
Application
Columns
Beams
Frames
Floors
Author
Moroder, Daniel
Buchanan, Andrew
Pampanin, Stefano
Publisher
New Zealand Timber Design Society
Year of Publication
2018
Country of Publication
New Zealand
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Application
Columns
Beams
Frames
Floors
Topic
Design and Systems
Seismic
Keywords
Beam-to-Column Joints
Connections
Horizontal Loading
Post-Tensioned
Earthquake
Language
English
Research Status
Complete
Series
New Zealand Timber Design Journal
Online Access
Free
Resource Link
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Seismic Design Options for Post-Tensioned Timber Walls

https://research.thinkwood.com/en/permalink/catalogue1853
Year of Publication
2018
Topic
Design and Systems
Seismic
Material
LVL (Laminated Veneer Lumber)
Application
Walls
Author
Iqbal, Asif
Pampanin, Stefano
Palermo, Alessandro
Buchanan, Andrew
Fragiacomo, Massimo
Publisher
New Zealand Timber Design Society
Year of Publication
2018
Country of Publication
New Zealand
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Application
Walls
Topic
Design and Systems
Seismic
Keywords
Earthquake
Post-Tensioned
Energy Dissipation
Multi-Storey
Language
English
Research Status
Complete
Series
New Zealand Timber Design Journal
Online Access
Free
Resource Link
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Shaking Table Testing of a Multi-Storey Post-Tensioned Glulam Building: Preliminary Experimental Results

https://research.thinkwood.com/en/permalink/catalogue1854
Year of Publication
2018
Topic
Seismic
Design and Systems
Material
Glulam (Glue-Laminated Timber)
Application
Frames
Beams
Columns

Timber Core-Walls for Lateral Load Resistance of Multi-Storey Timber Buildings

https://research.thinkwood.com/en/permalink/catalogue1858
Year of Publication
2018
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Dunbar, Andrew
Moroder, Daniel
Pampanin, Stefano
Buchanan, Andrew
Publisher
New Zealand Timber Design Society
Year of Publication
2018
Country of Publication
New Zealand
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Design and Systems
Seismic
Keywords
Pres-Lam
Earthquake
Post-Tensioned
Core-Walls
Multi-Storey
Panels
Language
English
Research Status
Complete
Series
New Zealand Timber Design Journal
Online Access
Free
Resource Link
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Higher Mode Effects in Multi-Storey Timber Buildings with Varying Diaphragm Flexibility

https://research.thinkwood.com/en/permalink/catalogue1480
Year of Publication
2017
Topic
Seismic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Frames
Walls
Author
Moroder, Daniel
Sarti, Francesco
Pampanin, Stefano
Smith, Tobias
Buchanan, Andrew
Year of Publication
2017
Country of Publication
New Zealand
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Frames
Walls
Topic
Seismic
Mechanical Properties
Keywords
Nonlinear Time History Analysis
Higher Mode Effects
Stiffness
Diaphragms
Inter-Story Drift
Language
English
Conference
New Zealand Society for Earthquake Engineering Conference
Research Status
Complete
Notes
April 27-29, 2017, Wellington, New Zealand
Summary
With the increasing acceptance and popularity of multi-storey timber buildings up to 10 storeys and beyond, the influence of higher mode effects and diaphragm stiffness cannot be overlooked in design. Due to the lower stiffness of timber lateral load resisting systems compared with traditional construction materials, the effect of higher modes on the global dynamic behaviour can be more critical. The presence of flexible timber diaphragms creates additional vibration modes, which have the potential to interact with each other, increasing the seismic demand on the whole structure. This paper uses a parametric non-linear time-history analysis on a series of timber frame and wall structures with varying diaphragm flexibility to study their dynamic behaviour and to determine diaphragm forces. The analyses results showed that although higher mode effects play a significant role in the structural dynamic response, this increased demand can be successfully predicted with methods available in literature. The parametric analyses showed that the diaphragm flexibility did not significantly increase the shear and moment demand; however, stiff wall structures with flexible diaphragms experienced large inter-storey drifts measured at diaphragm midspan compared with the drift of the wall alone. As expected, the diaphragm forces observed from the time-history analyses were significantly higher than the forces derived from an equivalent static analysis, leading to a potentially unsafe design. The paper presents a simplified approach for evaluating these amplified peak inertial diaphragm forces.
Online Access
Free
Resource Link
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Development and Testing of an Alternative Dissipative Posttensioned Rocking Timber Wall with Boundary Columns

https://research.thinkwood.com/en/permalink/catalogue1884
Year of Publication
2016
Topic
Seismic
Design and Systems
Application
Frames
Walls

NMIT Arts & Media Building—Innovative structural design of a three storey post-tensioned timber building

https://research.thinkwood.com/en/permalink/catalogue2851
Year of Publication
2016
Topic
Design and Systems
Material
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems
Shear Walls
Author
Holden, Tony
Devereux, Carl
Haydon, Shane
Buchanan, Andrew
Pampanin, Stefano
Organization
Aurecon New Zealand
PTL Structural Timber Consultants
University of Canterbury
Publisher
Elsevier
Year of Publication
2016
Country of Publication
New Zealand
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems
Shear Walls
Topic
Design and Systems
Keywords
Performance Based Design
Post-Tensioned Timber
Multi-Storey
Plastic Fuse
Language
English
Research Status
Complete
Series
Case Studies in Structural Engineering
Summary
The NMIT Arts & Media Building in Nelson, New Zealand is the first in a new generation of multi-storey timber structures. It employs a number of innovative timber technologies including an advanced damage avoidance earthquake design that is a world first for a timber building. Aurecon structural engineers are the first to use this revolutionary Pres-Lam technology developed at the University of Canterbury. This technology marks a fundamental change in design philosophy. Conventional seismic design of multi-storey structures typically depends on member ductility and the acceptance of a certain amount of damage to beams, columns or walls. The NMIT seismic system relies on pairs of coupled timber shear walls that incorporate high strength steel tendons post-tensioned through a central duct. The walls are centrally fixed allowing them to rock during a seismic event. A series of U-shaped steel plates placed between the walls form a coupling mechanism, and act as dissipaters to absorb seismic energy. The design allows the primary structure to remain essentially undamaged in a major earthquake while readily replaceable connections act as plastic fuses. With a key focus on sustainability the extensive use of timber and engineered-wood products such as laminated veneer lumber (LVL) makes use of a local natural resource, all grown and manufactured within an 80 km radius of Nelson. This IstructE award winning project demonstrates that there are now cost effective, sustainable and innovative solutions for multi-storey timber buildings with potential applications for building owners in seismic areas around the world.
Online Access
Free
Resource Link
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35 records – page 1 of 4.