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42 records – page 1 of 5.

Braced Frame System for Timber Buildings

https://research.thinkwood.com/en/permalink/catalogue2527
Year of Publication
2020
Topic
Design and Systems
Seismic
Material
Glulam (Glue-Laminated Timber)
Application
Hybrid Building Systems
Frames
Author
Iqbal, Asif
Organization
University of Northern British Columbia
Year of Publication
2020
Format
Report
Material
Glulam (Glue-Laminated Timber)
Application
Hybrid Building Systems
Frames
Topic
Design and Systems
Seismic
Keywords
Lateral Load Resisting Systems
Sustainability
Post-Tensioned
Connections
Braced Frame Model
Timber-Steel Hybrid
Research Status
Complete
Summary
Advanced sustainable lateral load resisting systems that combine ductile and recyclable materials offer a viable solution to resist seismic load effects in environmentally responsible ways. This paper presents the seismic response of a post-tensioned timber-steel hybrid braced frame. This hybrid system combines glulam frame with steel braces to improve lateral stiffness while providing self-centreing capability under seismic loads. The proposed system is first presented. A detailed numerical model of the proposed system is then developed with emphasis on the connections and inelastic response of bracing members. Various types of braced frames including diagonal, cross and chevron configurations are numerically examined to assess the viability of the proposed concept and to confirm the efficiency of the system. A summary of initial findings is presented to demonstrate usefulness of the hybrid system. The results demonstrate that the proposed system increases overall lateral stiffness and ductility while still being able to achieve self-centring. Some additional information on connection details are provided for implementation in practical structures. The braced-frame solution is expected to widen options for lateral load resisting systems for mid-to-high-rise buildings.
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Structural Design and Modelling Method for the Post-Tensioned CLT Shear Wall Structures

https://research.thinkwood.com/en/permalink/catalogue2149
Year of Publication
2019
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Walls

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
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
Research Status
Complete
Series
New Zealand Timber Design Journal
Summary
Post-tensioned rocking structures are known to perform well under seismic action, but as with most other structural systems, there is concern about possible damage to floor diaphragms. This is due to displacement incompatibilities, especially if frame elongation occurs due to gap opening at the beam-column-joints. This paper describes the experimental behaviour of an engineered timber floor connected to a post-tensioned timber frame subjected to horizontal seismic loading. A full scale two-bay post-tensioned frame was loaded with lateral loads, which were applied through a strip of floor diaphragm spanning perpendicular to the beams. Several different connection configurations between the floor portions on either side of the central column were tested. The diaphragm deformation demand adjacent to the beam-columnjoint gap opening was accommodated through two mechanisms: a concentrated floor gap opening at the column or a combination of panel elongation and small gap openings over a number of floor elements. In all the tests, only elastic deformations were observed and the diaphragm behaviour of the floor elements was fully maintained throughout the testing. The results showed that design to allow flexibility of timber elements combined with proper connection detailing can prevent damage at high level of drift to the floor diaphragms in post-tensioned timber frame buildings.
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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
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Application
Walls
Topic
Design and Systems
Seismic
Keywords
Earthquake
Post-Tensioned
Energy Dissipation
Multi-Storey
Research Status
Complete
Series
New Zealand Timber Design Journal
Summary
Structural systems made of prefabricated laminated timber members connected by unbonded post-tensioning and additional mild steel reinforcement have recently been proposed for multi-storey timber buildings. The benefits of the use of post-tensioning to assemble prefabricated timber elements are rapid erection, simple connections, and high seismic resistance. It has been shown that prefabricated post-tensioned timber members can be designed to have excellent seismic resistance, with the post-tensioning providing re-centering capacity after major earthquakes, while energy is dissipated through yielding of replaceable steel elements. Both post-tensioning and energy dissipating elements contribute to the stiffness and strength of the overall system. Investigation into the seismic response of twin post-tensioned timber walls, uncoupled and coupled, with and without energy dissipaters has been performed as part of a larger research programme on timber structures at the University of Canterbury. The walls were fabricated from laminated veneer lumber (LVL). A number of special fuses all made of mild steel were used as energy dissipating devices. The energy dissipaters are attached externally so that they can be removed and replaced easily after a major earthquake. Under gravity or low-seismic loading they would be able to provide, as per standard mild steel reinforcement, substantial stiffness and strength. As additional option, plywood sheets have been used to couple the LVL walls in which case the nails dissipated energy through yielding during rocking motion of the walls. This paper discusses the experimental tests and numerical validation of the response of posttensioned timber wall systems. The results show excellent seismic behaviour with very little residual damage. This research also demonstrates the practical feasibility of post-tensioned timber walls for multi-storey timber buildings as well as their versatility of design and use.
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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
Author
Carlo Ponzo, Felice
Di Cesare, Antonio
Nigro, Domenico
Simonetti, Michele
Smith, Tobias
Pampanin, Stefano
Publisher
New Zealand Timber Design Society
Year of Publication
2018
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Frames
Beams
Columns
Topic
Seismic
Design and Systems
Keywords
Post-Tensioned
Earthquake
Multi-Storey
Shaking Table Test
Pres-Lam
Hysteretic
Energy Dissipation
Seismic Loading
Research Status
Complete
Series
New Zealand Timber Design Journal
Summary
This paper describes the results of preliminary shaking table testing performed on a post-tensioned glulam framed building in the structural laboratory of the University of Basilicata in Potenza, Italy. This experimental campaign is part of a series of experimental tests in collaboration with the University of Canterbury in Christchurch, New Zealand. The specimen is 3-dimensional, 3-storey, 2/3rd scale and is made up of post-tensioned timber frames in both directions. During the testing programme the specimen was tested with and without the addition of dissipative steel angle reinforcing which was designed to yield at a certain level of frame drift. These steel angles release energy through hysteresis during movement thus increasing damping. The specimen was subjected to a selection of natural earthquake records with increasing (as % of PGA) levels of seismic loading. This paper briefly discusses the testing set-up and then presents the result of the first phase of experimental testing with and without additional reinforcing.
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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
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
Research Status
Complete
Series
New Zealand Timber Design Journal
Summary
This paper describes the results of experimental tests on post-tensioned Cross-Laminated Timber (CLT) corewalls tested under bi-directional quasi-static seismic loading. The half-scale two-storey test specimens included a stair with half-flight landings. The use of CLT panels for multi-storey timber buildings is gaining popularity throughout the world, especially for residential construction. Post-tensioned timber core-walls for lift-shafts (elevator shafts) or stairwells can be used as tubular structures for resistance to seismic loads and wind loads in open-plan commercial office bldings Previous experimental testing has been done on the in-plane behaviour of single and coupled timber walls at the University of Canterbury and elsewhere. However, there has been very little research done on the 3D behaviour of timber walls that are orthogonal to each other, and no research to date into single post-tensioned CLT walls or CLT tubular structures. This paper describes a “High Seismic option” consisting of full height post-tensioned CLT walls coupled with energy dissipating U-shaped Flexural Plates (UFPs) attached at the vertical joints between coupled wall panels and between wall panels and steel corner columns. An alternative “Low Seismic option” consists of posttensioned CLT panels connected by screws, to provide a semi-rigid connection, allowing relative movement between the panels, producing some level of frictional energy dissipation. The Low Seismic option is suitable for wind loading in non-(or low-) seismic regions.
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Free
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Seismic Performance of Post-Tensioned Moment-Resisting Portal Frames

https://research.thinkwood.com/en/permalink/catalogue1973
Year of Publication
2018
Topic
Seismic
Design and Systems
Material
Glulam (Glue-Laminated Timber)
Application
Frames
Wood Building Systems
Author
Chen, Zhiyong
Popovski, Marjan
Gerber, Adam
Year of Publication
2018
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Application
Frames
Wood Building Systems
Topic
Seismic
Design and Systems
Keywords
Post-Tensioned
Moment-Resisting
Seismic Performance
Cyclic Tests
Portal Frames
Conference
World Conference on Timber Engineering
Research Status
Complete
Summary
Glulam-based post-tensioned moment-resisting portal frames were developed by a producer from British Columbia in collaboration with ASPECT Structural Engineers. These modular frames, manufactured from appearance-grade glulam, can be viable solutions for substitution of steel moment frames in predominantly wood-framed buildings. This paper presents an experimental study on the structural performance of post-tensioned glulam moment-resisting portal frames under in-plane lateral loads. A total of twelve frame specimens in four different configurations were tested under static or reversed cyclic loads. The test results show that the behaviour of post-tensioned moment-resisting portal frames was relatively similar under static and cyclic loading, in which non-linear elastic behaviour was observed due to the post-tensioning. The peak lateral loads applied to the tested post-tensioned frames was in a range of 34.1 kN to 61.7 kN and the lateral stiffness ranged from 0.53 kN/mm to 2.65 kN/mm, respectively. Depending of the frame configuration, typical failure modes identified during the testing consisted of a combination of either (i) compression perpendicular to grain failure at the columns on the side in contact with the beam; or (ii) compression perpendicular to grain failure at the beam on the side in contact with the columns; and (iii) screw failure in the column-to-base joints (if present). The tests give a valuable insight into the seismic performance of post-tensioned glulam moment-resisting portal frames.
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Dynamic Response of an Under-Deck Cable-Stayed Timber-Concrete Composite Bridge Under a Moving Load

https://research.thinkwood.com/en/permalink/catalogue2037
Year of Publication
2018
Topic
Mechanical Properties
Design and Systems
Material
Timber-Concrete Composite
Application
Bridges and Spans
Author
Lyu, Zhan
MÁLAGA-CHUQUITAYPE, Christian
Ruiz-Teran, Ana
Organization
Imperial College London
Year of Publication
2018
Format
Conference Paper
Material
Timber-Concrete Composite
Application
Bridges and Spans
Topic
Mechanical Properties
Design and Systems
Keywords
FE model
Post-Tensioned
Shear Deformations
Deflection
Shear Forces
Dynamic Response
Conference
World Conference on Timber Engineering
Research Status
Complete
Summary
Timber-Concrete Composite bridges have the potential to achieve significant levels of structural efficiency through the synergistic use of Engineering Wood Products (EWPs) and reinforced concrete. With the implementation of post-tensioned under-deck tendons, the range of application of TCC bridges can be extended to medium spans. However, little work has been done to date to study the dynamic response of these newly proposed bridges. In this paper, a set of FE models representing 60-m span structures are analysed to gain understanding on the dynamic response of post-tensioned under-deck TCC bridges. Two models with Euler and Timoshenko beam idealizations are considered in order to evaluate the significance of shear deformations on deflection, structural stresses and connector shear forces. Besides, an analytical model is formulated and compared against the numerical predictions. The results show that timber shear deformations should be considered in the design of post-tensioned under-deck TCC bridges. The dynamic characteristics of the bridge models were studied. The dynamic amplification caused by a moving point load on key response parameters such as deflection, stresses and connector shear forces is discussed. Also, a sensitivity study on the speed of moving load is conducted to investigate its influence on the bridge dynamic response.
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Free
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Full-Scale Shake Table Test of a Two-story Mass-Timber Building with Resilient Rocking Walls

https://research.thinkwood.com/en/permalink/catalogue2067
Year of Publication
2018
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Author
Pei, Shiling
van de Lindt, John
Barbosa, André
Berman, Jeffrey
Blomgren, Hans-Erik
Dolan, James
McDonnell, Eric
Zimmerman, Reid
Fragiacomo, Massimo
Rammer, Douglas
Organization
Colorado School of Mines
Colorado State University
Oregon State University
University of Washington
Washington State University
University of L’Aquila
Year of Publication
2018
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Topic
Seismic
Keywords
Shake Table Test
Multi-Story
Post-Tensioned
Rocking Walls
Conference
16th European Conference on Earthquake Engineering
Research Status
Complete
Summary
The NHERI TallWood project is a U.S. National Science Foundation-funded four-year research project focusing on the development of a resilient tall wood building design philosophy. One of the first major tasks within the project was to test a full-scale two-story mass timber building at the largest shake table in the U.S., the NHERI at UCSD’s outdoor shake table facility, to study the dynamic behaviour of a mass timber building with a resilient rocking wall system. The specimen consisted of two coupled two-story tall post-tensioned cross laminated timber rocking walls surrounded by mass timber gravity frames simulating a realistic portion of a building floor plan at full scale. Diaphragms consisted of bare CLT at the first floor level and concrete-topped, composite CLT at the roof. The specimen was subjected to ground motions scaled to three intensity levels representing frequent, design basis, and maximum considered earthquakes. In this paper, the design and implementation of this test program is summarized. The performance of the full building system under these different levels of seismic intensity is presented.
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Free
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Performance of Post-Tensioned Timber and Engineered Timber Adhesives with Fire Exposure

https://research.thinkwood.com/en/permalink/catalogue2220
Year of Publication
2018
Topic
Fire
Material
Glulam (Glue-Laminated Timber)
LVL (Laminated Veneer Lumber)
Application
Beams

42 records – page 1 of 5.