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The Design of a Semi-Prefabricated LVL-Concrete Composite Floor

https://research.thinkwood.com/en/permalink/catalogue103
Year of Publication
2012
Topic
Design and Systems
Material
LVL (Laminated Veneer Lumber)
Timber-Concrete Composite
Application
Floors
Author
Yeoh, David
Fragiacomo, Massimo
Publisher
Hindawi Publishing Corporation
Year of Publication
2012
Country of Publication
Egypt
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Timber-Concrete Composite
Application
Floors
Topic
Design and Systems
Keywords
Flexural Stiffness Method
Prefabrication
Language
English
Research Status
Complete
Series
Advances in Civil Engineering
Summary
This paper describes the design of a novel semi-prefabricated LVL-concrete composite floor that has been developed in New Zealand. In this solution, the floor units made from LVL joists and plywood are prefabricated in the factory and transported to the building site. The units are then lifted onto the supports and connected to the main frames of the building and to the adjacent units. Finally, a concrete topping is poured on top of the units in order to form a continuous slab connecting all the units. Rectangular notches cut from the LVL joists and reinforced with coach screws provide the composite action between the concrete slab and the LVL joists. This system proved to be an effective modular solution that ensures rapid construction. A design procedure based on the use of the effective flexural stiffness method, also known as the “gamma method” is proposed for the design of the composite floor at ultimate and serviceability limit states, in the short and long term. By comparison with the experimental results, it is shown that the proposed method leads to conservative design. A step-by-step design worked example of this novel semi-prefabricated composite floor concludes the paper.
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Effect of Flexible Supports on Vibration Performance of Timber Floors

https://research.thinkwood.com/en/permalink/catalogue190
Year of Publication
2012
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Floors
Author
Jarnerö, Kirsi
Bolmsvik, Åsa
Brandt, Anders
Olsson, Anders
Organization
Euronoise
Year of Publication
2012
Country of Publication
Czech Republic
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Floors
Topic
Acoustics and Vibration
Keywords
Residential
Multi-Storey
Noise
Prefabrication
In Situ
Vibration
Damping
Interlayer
Language
English
Conference
Ninth European Conference on Noise Control (Euronoise)
Research Status
Complete
Notes
June 10-13, 2012, Prague, Czech Republic
Summary
In residential multi-storey buildings of timber it is of great importance to reduce the flanking transmission of noise. Some building systems do this by installing a vibration-damping elastic interlayer, Sylomer or Sylodyn , in the junction between the support and the floor structure. This interlayer also improves the floor vibration performance by adding damping to the structure. In the present work the vibration performance of a floor with such interlayers has been investigated both in laboratory and field tests. A prefabricated timber floor element was tested in laboratory on rigid supports and on supports with four different types of interlayers. The results are compared with in situ tests on a copy of the same floor element. The effect on vibration performance i.e. frequencies, damping ratio and mode shapes is studied. A comparison of the in situ test and the test with elastic interlayer in laboratory shows that the damping in situ is approximately three times higher than on a single floor element in the lab. This indicates that the damping in situ is affected be the surrounding building structure. The achieved damping ratio is highly dependent on the mode shapes. Mode shapes that have high mode shape coefficients along the edges where the interlayer material is located, result in higher modal damping ratios. The impulse velocity response, that is used to evaluate the vibration performance and rate experienced annoyance in the design of wooden joist floors, seems to be reduced when adding elastic layers at the supports.
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Expanding Opportunities for Mid-Rise Buildings in Chile through the Application of Timber Panel Systems

https://research.thinkwood.com/en/permalink/catalogue193
Year of Publication
2012
Topic
Market and Adoption
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Rivera, Cristián
Organization
University of British Columbia
Year of Publication
2012
Country of Publication
Canada
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Market and Adoption
Seismic
Keywords
Chile
Codes
Mid-Rise
Prefabrication
City Densification
Language
English
Research Status
Complete
Summary
During the last few years, the merging of timber building tradition with the application of new technologies has produced new prefabricated building systems in Europe and North America. Mid-rise buildings present a unique opportunity to apply new timber technologies. Chile has shown sustained growth of buildings construction during the past decades but little further development in the use of wood. To establish the feasibility of timber systems applied to the Chilean context this research considered social aspects, technical aspects and local standards related to the manufacture and construction using timber components. A project proposal is used to analyze the architectural applications of timber systems according to the Chilean context. The design considers the case of densification in the city of Santiago and investigates the possibility of developing mid-rise structures using the structural properties and features of timber systems. So far only two systems applied to mid-rise structures have been tested for seismic resistance on full scale prototypes: Midply and Cross Laminated Timber.
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Prefabricated Timber-Concrete Composite System

https://research.thinkwood.com/en/permalink/catalogue910
Year of Publication
2012
Topic
Design and Systems
Mechanical Properties
Connections
Material
Timber-Concrete Composite
Application
Floors
Author
Moar, Franco
Organization
Lund University
Year of Publication
2012
Country of Publication
Sweden
Format
Thesis
Material
Timber-Concrete Composite
Application
Floors
Topic
Design and Systems
Mechanical Properties
Connections
Keywords
FE model
Bending Tests
Withdrawal Tests
Compression Tests
Self-Tapping Screws
Prefabrication
Language
English
Research Status
Complete
Summary
Timber-concrete composite structures were originally developed for upgrading existing timber oors, but during last decades, they have new applications in multistorey buildings. Most of the research performed on these structures has focused on systems in which wet concrete is cast on top of timber beams with mounted connectors. Recently investigations on composite systems were performed at Luleå University of Technology in Sweden, in which the concrete slab is prefabricated off-site with the connectors already embedded and then connected on-site to the timber joists. Similar studies have been carried out also on timber-concrete composite structures with prefabricated FRC slabs at Lund University in Sweden. Two kinds of shear connectors were incorporated in the prefabricated FRC concrete slabs. These last systems can be considered globally as partially prefabricated structures because only the slabs were cast off-site with already inserted shear connectors and then the connection with the timber beams is done on the building site. An innovative composite system for floor applications is presented in this thesis. The entire structure is prefabricated off-side, transported and direct mounted to the building on site, that can be seen as full prefabricated structures. Noticeable benefits of a full prefabricated structure are that the moving work from the building site to the workshop reduces construction costs, is more simple and fast of manufacture and erect, and of sure, has better quality, that means more durability. Self-tapping full-threaded screws to connect concrete slabs to timber beam were used. Dimensions of the composite beams and the spacing between the screws has been chosen by discussing different FE model in order to reach the optimal solution. The experimental campaign included: (i) two short-time bending tests carried out on two dierent full-scale specimens, (ii) dynamic tests conducted on one full-scale specimen, (iii) long-time bending test carried out on one full-scale specimen, (iv) compression tests on three cubes of concrete, (v) nine withdrawal tests of the screws with different depth in the concrete. The results of the experimental tests show that the composite beams have a very high level of resistance and stiffness and also allow to reach a high degree of efficiency. Last, comparisons between FE results, analytical calculations and experimental values have been performed and from them it can be concluded that FE model and theoretical calculations well interpret the behavior of the composite structure and provide reliable results.
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Development of a Slab-on-Girder Wood-Concrete Composite Highway Bridge

https://research.thinkwood.com/en/permalink/catalogue1421
Year of Publication
2012
Topic
Design and Systems
Material
Glulam (Glue-Laminated Timber)
Application
Bridges and Spans
Author
Lehan, Andrew
Organization
University of Toronto
Year of Publication
2012
Country of Publication
Canada
Format
Thesis
Material
Glulam (Glue-Laminated Timber)
Application
Bridges and Spans
Topic
Design and Systems
Keywords
Ultra-High-Performance Fibre-Reinforced Concrete
Girder
Post-Tensioning
Prefabrication
Durability
Span-to-Depth Ratio
Language
English
Research Status
Complete
Summary
This thesis examines the development of a superstructure for a slab-on-girder wood-concrete composite highway bridge. Wood-concrete composite bridges have existed since the 1930's. Historically, they have been limited to spans of less than 10 m. Renewed research interest over the past two decades has shown great potential for longer span capabilities. Through composite action and suitable detailing, improvements in strength, stiffness, and durability can be achieved versus conventional wood bridges. The bridge makes use of a slender ultra-high performance fibre-reinforced concrete (UHPFRC) deck made partially-composite in longitudinal bending with glued-laminated wood girders. Longitudinal external unbonded post-tensioning is utilized to increase span capabilities. Prefabrication using double-T modules minimizes the need for cast-in-place concrete on-site. Durability is realized through the highly impermeable deck slab that protects the girders from moisture. Results show that the system can span up to 30 m while achieving span-to-depth ratios equivalent or better than competing slab-on-girder bridges.
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Seismic Design of Core-Walls for Multi-Storey Timber Buildings

https://research.thinkwood.com/en/permalink/catalogue134
Year of Publication
2013
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shafts and Chases
Author
Dunbar, Andrew
Pampanin, Stefano
Palermo, Alessandro
Buchanan, Andrew
Year of Publication
2013
Country of Publication
New Zealand
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Shafts and Chases
Topic
Design and Systems
Seismic
Keywords
Multi-Storey
Prefabrication
Pres-Lam
Residential
Quasi-Static Loading
Energy Dissipation
U-Shaped Flexural Plates
Language
English
Conference
New Zealand Society for Earthquake Engineering Conference
Research Status
Complete
Notes
April 26-28, 2013, Wellington, New Zealand
Summary
This paper describes options for seismic design of pre-fabricated timber core-wall systems, used as stairwells and lift shafts for lateral load resistance in multi-storey timber buildings. The use of Cross-Laminated Timber (CLT) panels for multi-storey timber buildings is gaining popularity throughout the world, especially for residential construction. This paper describes the possible use of CLT core-walls for seismic resistance in open-plan commercial office buildings in New Zealand. Previous experimental testing at the University of Canterbury has been done on the in-plane behaviour of single and coupled Pres-Lam post-tensioned timber walls. However there has been very little research done on the behaviour of timber walls that are orthogonal to each other and no research into CLT walls in the post-tensioned Pres-Lam system. This paper describes the proposed test regime and design detailing of two half-scale twostorey CLT stairwells to be tested under a bi-directional quasi-static loading. The test specimens will include a half-flight stair case with landings within the stairwell. The “High seismic option” consists of post-tensioned CLT walls coupled with energy dissipating U-shaped Flexural Plates (UFP) attached between wall panels and square hollow section steel columns at the corner junctions. An alternative “Low seismic option” uses the same post-tensioned CLT panels, with no corner columns or UFPs. The panels will be connected by screws to provide a semi-rigid connection, allowing relative movement between the panels producing some level of energy dissipation.
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In Situ Measured Flanking Transmission in Light Weight Timber Houses with Elastic Flanking Isolators

https://research.thinkwood.com/en/permalink/catalogue231
Year of Publication
2013
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
Application
Floors
Wood Building Systems
Author
Ågren, Anders
Ljunggren, Fredrik
Organization
Inter-noise
Year of Publication
2013
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Floors
Wood Building Systems
Topic
Acoustics and Vibration
Keywords
Modules
Prefabrication
Sound Insulation
Elastomer Isolators
Language
English
Conference
Inter-noise 2013
Research Status
Complete
Notes
September 15-18, 2013, Innsbruck, Austria
Summary
There is a strong trend to industrially produce multi-storey light weight timber based houses. This concept allows the buildings to be manufactured to a more or less prefabricated extent. Most common types are volume/room modules or flat wall and floor modules. When assembling the modules at the building site, elastomer isolators are used in several constructions to reduce flanking transmission. The sound insulation demands in the Nordic countries are relatively high and therefore the flanking transmission must be well controlled, where elastomer isolators are an alternative. Decoupled radiation isolated walls is another. There are though no working studies or mathematical models of the performance of these isolators. They are only treated as simple mass-springs systems that operate vertically, i.e. one degree of freedom. In this paper there is an analysis of experimentally data of the structure borne sound isolating performance of elastomer isolators that are separating an excited floor from receiving walls. The performance dependence of structure type is also presented. An empirically based regression model of the vibration level difference is derived. The model is based on measurements of six elastomer field installations, which are compared to five comparable installations without elastomers. A goal is that the model can be used for input in future SEN prediction models for modeling of sound insulation.
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Cross-Laminated Timber for Seismic Regions: Progress and Challenges for Research and Implementation

https://research.thinkwood.com/en/permalink/catalogue162
Year of Publication
2014
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Author
Pei, Shiling
van de Lindt, John
Popovski, Marjan
Berman, Jeffrey
Dolan, Daniel
Ricles, James
Sause, Richard
Blomgren, Hans-Erik
Rammer, Douglas
Publisher
American Society of Civil Engineers
Year of Publication
2014
Country of Publication
United States
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Topic
Seismic
Keywords
Lateral Loads
Prefabrication
US
Language
English
Research Status
Complete
Series
Journal of Structural Engineering
Summary
Compared to light-frame wood shear walls, it is relatively difficult for panelized CLT shear walls to achieve similar levels of lateral deflection without paying special attention to design details, i.e., connections. A design lacking ductility or energy dissipating mechanism will result in high acceleration amplifications and excessive global overturning demands for multistory buildings, and even more so for tall wood buildings. Although a number of studies have been conducted on CLT shear walls and building assemblies since the 1990s, the wood design community’s understanding of the seismic behavior of panelized CLT systems is still in the learning phase, hence the impetus for this article and the tall CLT building workshop, which will be introduced herein. For example, there has been a recent trend in engineering to improve resiliency, which seeks to design a building system such that it can be restored to normal functionality sooner after an earthquake than previously possible, i.e., it is a resilient system. While various resilient lateral system concepts have been explored for concrete and steel construction, this concept has not yet been realized for multistory CLT systems. This forum article presents a review of past research developments on CLT as a lateral force-resisting system, the current trend toward design and construction of tall buildings with CLT worldwide, and attempts to summarize the societal needs and challenges in developing resilient CLT construction in regions of high seismicity in the United States.
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An Innovative Connection System for CLT Structures: Experimental - Numerical Analysis

https://research.thinkwood.com/en/permalink/catalogue460
Year of Publication
2014
Topic
Connections
Material
CLT (Cross-Laminated Timber)
Author
Polastri, Andrea
Angeli, Albino
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Topic
Connections
Keywords
Prefabrication
Self-Tapping Screws
X-RAD
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
The paper describes experimental and numerical analyses on a completely new connection system developed for CLT (Cross Laminated Timber) constructions. The innovative solution herein proposed, named X-RAD, consists of a point-to-point mechanical connection system, fixed to the corners of the CLT panels. This connection, that is designed to be prefabricated, is made of a metal wrapping and an inner hard wood element which are fastened to the panel by means of allthreaded self-tapping screws. Such system permits to reduce significantly the number of bolts/fasteners required to assemble two or more panels together or to connect them to the foundation. This results in the enhancement of the installation process in terms of speed, quality and safety. One of the reasons that fuelled the development of the presented system, is the desire of offering a solution to those issues (e.g. to satisfy ductility and energetic dissipation requirements) commonly related to the seismic safety of timber structures. In other words there was the will of defining a system able to guarantee an adequate level of ductility and energetic dissipation.
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Development of a Wooden Adaptive Architectural System: A Design-Build Approach

https://research.thinkwood.com/en/permalink/catalogue486
Year of Publication
2014
Topic
Design and Systems
Material
LSL (Laminated Strand Lumber)
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems
Author
Potvin, André
Demers, Claude
DuMontier, Cédric
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
LSL (Laminated Strand Lumber)
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems
Topic
Design and Systems
Keywords
Computer Numerically Controlled
Manufacturing
Prefabrication
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
The design-build of a Wooden Adaptive Architectural System is part of a larger research-creation project on Adaptive Architecture (AA) [1] exploring the entire design process leading to a fully adaptable three story high 1:3/4 wooden structure. This system allows the easy manoeuvrability by the occupants of walls and floors in x, y and z directions in order to adapt the space to their environmental and functional needs. The omnidirectional mobility criteria challenged conventional building techniques and led to an innovative all-wood rigid node. Extensive prototyping using digital fabrication allowed the team to optimize the node assemblage and precision through parametric experimentation before proper production. The Wooden Adaptive Architectural System, made of 2000 prefabricated sticks measuring as little as 1 ¾” x 1 ¾” x 24” provides fully adaptive space configurations and be easily deconstructed, transported, and reassembled in totally new building shapes.
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61 records – page 1 of 7.