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166 records – page 1 of 17.

100-Year Performance of Timber-Concrete Composite Bridges in the United States

https://research.thinkwood.com/en/permalink/catalogue2561
Year of Publication
2020
Topic
Serviceability
Application
Bridges and Spans
Author
Wacker, James
Dias, Alfredo
Hosteng, Travis
Year of Publication
2020
Format
Journal Article
Application
Bridges and Spans
Topic
Serviceability
Keywords
Concrete
Composite
Superstructure
Performance
Inspection
Research Status
Complete
Series
Journal of Bridge Engineering
Summary
The use of timber–concrete composite (TCC) bridges in the United States dates back to approximately 1924 when the first bridge was constructed. Since then a large number of bridges have been built, of which more than 1,400 remain in service. The oldest bridges still in service are now more than 84 years old and predominately consist of two different TCC systems. The first system is a slab-type system that includes a longitudinal nail-laminated deck composite with a concrete deck top layer. The second system is a stringer system that includes either sawn timber or glulam stringers supporting a concrete deck top layer. The records indicate that most of the TCC highway bridges were constructed during the period of 1930–1960. The study presented in this paper discusses the experience and per-formance of these bridge systems in the US. The analysis is based on a review of the relevant literature and databases complemented with field inspections conducted within various research projects. Along with this review, a historical overview of the codes and guidelines available for the design of TCC bridges in the US is also included. The analysis undertaken showed that TCC bridges are an effective and durable design alternative for highway bridges once they have shown a high performance level, in some situations after more than 80 years in service with a low maintenance level.
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Achieving Sustainable Urban Buildings with Seismically Resilient Mass Timber Core Wall and Floor System

https://research.thinkwood.com/en/permalink/catalogue2802
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Cores
Walls
Floors
Wood Building Systems
Organization
Portland State University
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Cores
Walls
Floors
Wood Building Systems
Topic
Design and Systems
Seismic
Keywords
Hold-Down
Seismic Performance
Core Walls
Parametric Analysis
Deformation Capacity
Overstrength
Mid-Rise
High-Rise
Tall Wood Buildings
Research Status
In Progress
Notes
Project contact is Peter Dusicka at Portland State University
Summary
The urgency in increasing growth in densely populated urban areas, reducing the carbon footprint of new buildings, and targeting rapid return to occupancy following disastrous earthquakes has created a need to reexamine the structural systems of mid- to high-rise buildings. To address these sustainability and seismic resiliency needs, the objective of this research is to enable an all-timber material system in a way that will include architectural as well as structural considerations. Utilization of mass timber is societally important in providing buildings that store, instead of generate, carbon and increase the economic opportunity for depressed timber-producing regions of the country. This research will focus on buildings with core walls because those building types are some of the most common for contemporary urban mid- to high-rise construction. The open floor layout will allow for commercial and mixed-use occupancies, but also will contain significant technical knowledge gaps hindering their implementation with mass timber. The research plan has been formulated to fill these gaps by: (1) developing suitable mid- to high-rise archetypes with input from multiple stakeholders, (2) conducting parametric system-level seismic performance investigations, (3) developing new critical components, (4) validating the performance with large-scale experimentation, and (5) bridging the industry information gaps by incorporating teaching modules within an existing educational and outreach framework. Situated in the heart of a timber-producing region, the multi-disciplinary team will utilize the local design professional community with timber experience and Portland State University's recently implemented Green Building Scholars program to deliver technical outcomes that directly impact the surrounding environment. Research outcomes will advance knowledge at the system performance level as well as at the critical component level. The investigated building system will incorporate cross laminated timber cores, floors, and glulam structural members. Using mass timber will present challenges in effectively achieving the goal of desirable seismic performance, especially seismic resiliency. These challenges will be addressed at the system level by a unique combination of core rocking combined with beam and floor interaction to achieve non-linear elastic behavior. This system behavior will eliminate the need for post-tensioning to achieve re-centering, but will introduce new parameters that can directly influence the lateral behavior. This research will study the effects of these parameters on the overall building behavior and will develop a methodology in which designers could use these parameters to strategically control the building seismic response. These key parameters will be investigated using parametric numerical analyses as well as large-scale, sub-system experimentation. One of the critical components of the system will be the hold-down, a device that connects the timber core to the foundation and provides hysteretic energy dissipation. Strength requirements and deformation demands in mid- to high-rise buildings, along with integration with mass timber, will necessitate the advancement of knowledge in developing this low-damage component. The investigated hold-down will have large deformation capability with readily replaceable parts. Moreover, the hold-down will have the potential to reduce strength of the component in a controlled and repeatable way at large deformations, while maintaining original strength at low deformations. This component characteristic can reduce the overall system overstrength, which in turn will have beneficial economic implications. Reducing the carbon footprint of new construction, linking rural and urban economies, and increasing the longevity of buildings in seismic zones are all goals that this mass timber research will advance and will be critical to the sustainable development of cities moving forward.
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Acoustical Performance of Mass Timber Building Elements

https://research.thinkwood.com/en/permalink/catalogue2553
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
DLT (Dowel Laminated Timber)
NLT (Nail-Laminated Timber)
Application
Floors
Walls
Material
CLT (Cross-Laminated Timber)
DLT (Dowel Laminated Timber)
NLT (Nail-Laminated Timber)
Application
Floors
Walls
Topic
Acoustics and Vibration
Keywords
Sound Insulation
Acoustic Membrane
Acoustical Performance
Research Status
In Progress
Notes
Project contact is Jianhui Zhou at the University of Northern British Columbia
Summary
Building acoustics has been identified as one of the key subjects for the success of mass timber in the multi-storey building markets. The project will investigate the acoustical performance of mass timber panels produced in British Columbia. The apparent sound transmission class (ASTC) and impact insulation class (AIIC) of bare mass timber elements as wall and/ or floor elements will be measured through a lab mock-up. It is expected that a database of the sound insulation performance of British Columbia mass timber products will be developed with guidance on optimal acoustical treatments to achieve different levels of performance.
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Advanced Quality and In-Service Condition Assessment Procedures for Mass Timber and Cross-Laminated Timber Products

https://research.thinkwood.com/en/permalink/catalogue2558
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Organization
Forest Products Laboratory
Mississippi State University
Material
CLT (Cross-Laminated Timber)
Topic
Mechanical Properties
Keywords
Non-Destructive Evaluation
Bond Performance
Monitoring Techniques
Serviceability
Quality Assurance
Research Status
In Progress
Notes
Project contacts are Frederico França at Mississippi State University and Robert J. Ross at the Forest Products Laboratory
Summary
With the rapid development of CLT manufacturing capacity around the world and the increasing architectural acceptance and adoption, there is a current and pressing need regarding adhesive bond quality assurance in manufacturing. As with other engineered glued composites, adhesive bondline performance is critically important. Bondline assessment requires technology in the form of sensors, ultrasonics, load cells, or other means of reliable machine evaluation. The objectives of this cooperative study are to develop quality assurance procedures for monitoring the quality of mass timber and CLT during and after manufacturing and to develop assessment techniques for CLT panels in-service.
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Advanced Wood-Based Solutions for Mid-Rise and High-Rise Construction: In-Situ Testing of The Arbora Building for Vibration and Acoustic Performances

https://research.thinkwood.com/en/permalink/catalogue1179
Year of Publication
2018
Topic
Acoustics and Vibration
Design and Systems
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Author
Hu, Lin
Cuerrier-Auclair, Samuel
Organization
FPInnovations
Year of Publication
2018
Format
Report
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Topic
Acoustics and Vibration
Design and Systems
Keywords
Sound Insulation
Tall Wood
Vibration Performance
Mid-Rise
Research Status
Complete
Summary
This report addresses serviceability issues of tall wood buildings focusing on vibration and sound insulation performance. The sound insulation and vibration performance may not affect building's safety, but affects occupants' comfort and proper operation of the buildings and the funciton of sensitive equipment, consequently the acceptance of midrise and tall wood buildings in market place. Lack of data, knowledge and experience of sound and vibration performance of tall wood buildings is one of the issues related to design and construction of tall wood buildings.
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Advanced Wood-Based Solutions for Mid-Rise and High-Rise Construction: In-Situ Testing of the Brock Commons 18-Storey Building for Vibration and Acoustic performances

https://research.thinkwood.com/en/permalink/catalogue1180
Year of Publication
2018
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Author
Hu, Lin
Cuerrier-Auclair, Samuel
Organization
FPInnovations
Year of Publication
2018
Format
Report
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Topic
Acoustics and Vibration
Keywords
Non-Destructive Testing
Vibration Performance
Natural Frequencies
Damping Ratios
Sound Insulation
Ambient Vibration Testing
Apparent Sound Transmission Class
Research Status
Complete
Summary
This report addresses serviceability issues of tall wood buildings focusing on their vibration and sound insulation performance. The sound insulation and vibration performance may not affect the building’s safety, but affects the occupants’ comfort and the proper operation of the buildings and the function of sensitive equipment, consequently the acceptance of the midrise and tall wood buildings in market place. Lack of data, knowledge and experience of sound and vibration performance of tall wood buildings is one of the issues related to design and construction of tall wood buildings. The measured and estimated values should also be correlated with actual experiences of the occupants in the building if such information is obtained, for example, through a survey.
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Free
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Ambient and Forced Vibration Testing and Finite Element Model Updating of a Full-Scale Posttensioned Laminated Veneer Lumber Building

https://research.thinkwood.com/en/permalink/catalogue1103
Year of Publication
2012
Topic
Seismic
Wind
Acoustics and Vibration
Material
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems
Shear Walls
Author
Worth, Margaret
Omenzetter, Piotr
Morris, Hugh
Year of Publication
2012
Format
Conference Paper
Material
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems
Shear Walls
Topic
Seismic
Wind
Acoustics and Vibration
Keywords
Post-Tensioned
Full Scale
In Situ
Finite Element Model
Dynamic Performance
Conference
New Zealand Society for Earthquake Engineering Conference
Research Status
Complete
Notes
April 13-15, 2012, Christchurch, New Zealand
Summary
The Nelson Marlborough Institute of Technology Arts and Media building was completed in 2011 and consists of three seismically separate complexes. This research focussed on the Arts building as it showcases the use of coupled post-tensioned timber shear walls. These are part of the innovative Expan system. Full-scale, in-situ dynamic testing of the novel building was combined with finite element modelling and updating to obtain an understanding of the structural dynamic performance within the linear range. Ambient testing was performed at three stages during construction and was combined with forced vibration testing for the final stage. This forms part of a larger instrumentation program developed to investigate the wind and seismic response and long term deformations of the building. A finite element model of the building was formulated and updated using experimental modal characteristics. It was shown that the addition of non-structural elements, such as cladding and the staircase, increased the natural frequency of the first mode and the second mode by 19% and 24%, respectively. The addition of the concrete floor topping as a structural diaphragm significantly increased the natural frequency of the first mode but not the second mode, with an increase of 123% and 18%, respectively. The elastic damping of the NMIT building at low-level vibrations was identified as being between 1.6% and 2.4%
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Analyse de Performance Acoustique et de Résistance au Feu

https://research.thinkwood.com/en/permalink/catalogue2752
Year of Publication
2018
Topic
Acoustics and Vibration
Fire
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Organization
Société en commandite NEB
Year of Publication
2018
Format
Report
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Topic
Acoustics and Vibration
Fire
Keywords
Origine
Fire Resistance
Acoustic Performance
Tall Timber
Multi-Storey
Research Status
Complete
Summary
Le présent rapport décrit une partie des activités de recherche et développement (R&D) en lien avec la démonstration de la résistance au feu ainsi que les études sur la performance acoustique effectuées dans le cadre de la construction du bâtiment Origine. Ce bâtiment est la tour résidentielle en bois massif la plus haute au Québec. Sa réalisation a débuté en 2015 à la suite des analyses préliminaires de faisabilité technique-économique qui se sont étalées pendant toute l’année 2014. La construction et l’installation se sont finalisées vers la fin de 2017. En premier lieu, le rapport présente les démarches liées à la réalisation d’un exercice de démonstration d’incendie pour une cage d’escaliers/ascenseur avec une chambre d’habitation adjacente, l’analyse de résultats et les principales conclusions en lien avec la pertinence de l’utilisation du bois massif pour des édifices de grande hauteur. En ce qui concerne la performance acoustique, le rapport présente la méthodologie d’étude et d’analyse des résultats des tests acoustiques pour des assemblages de mur et de plancher utilisés dans le projet Origine. De plus, ce rapport facilite la compréhension des activités réalisées et permet de montrer objectivement la capacité des produits en bois massif à offrir un environnement sécuritaire et confortable aux occupants de bâtiments multi-étagés. Les principaux résultats indiquent que les cages d’escaliers/ascenseur faites en bois massif, conçues pour une résistance au feu équivalente à celle faites en béton, peuvent offrir une excellente performance et servent d’alternatives adéquates pour les bâtiments multi-étagés. En ce qui concerne le développement d’assemblages acoustiques pour les murs et les planchers en bois massif, il a été prouvé qu’une approche multicritère permet d’offrir des solutions performantes à des coûts raisonnables. Finalement, il est clair que ce projet constitue un jalon très important dans le chemin d’acceptation des bâtiments multi-étagés en bois massif au Québec et au Canada. Sa construction, faite presque entièrement en bois, a nécessité de nombreux efforts économiques, de R&D, de conception et d’installation. De plus, les activités réalisées pour l’acceptation de ce type de construction ont permis de mettre en place de nouvelles technologies et des techniques de conception qui faciliteront la réplication de ce type de projet partout en Amérique du Nord.
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Free
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An experimental and modeling study on apparent bending moduli of cross-laminated bamboo and timber (CLBT) in orthogonal strength directions

https://research.thinkwood.com/en/permalink/catalogue2914
Year of Publication
2022
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Li, Hao
Wang, Brad
Wang, Libin
Wei, Yang
Organization
Nanjing Forestry University
Southwest Forestry University
Publisher
Elsevier
Year of Publication
2022
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Mechanical Properties
Keywords
Bending Performance
Modeling Analysis
Cross-laminated Bamboo and Timber
Research Status
Complete
Series
Case Study in Construction Materials
Summary
In this paper, the bending properties of a 3-ply cross-laminated bamboo and timber (CLBT), prefabricated with the bamboo mat-curtain panel and hem-fir lumber, were examined in the major and minor strength directions, and a 3-ply hem-fir cross-laminated timber (CLT) was taken as a control group. The analytical model for the sum of the orthogonal apparent bending moduli with the two types of layer classifications were proposed, and the two kinds of contribution models were developed to analyze the apparent bending modulus variation behavior of the CLBT and CLT panels in the major and minor strength directions. The experimental results showed that since the CLBT group had more internal orthogonal structures, its difference in the bending properties between the major and minor strength directions was lower than that of the CLT group. Furthermore, the proposed contribution models quantitatively analyzed the relationship between the apparent bending moduli of the CLBT and CLT panels and the corresponding composition layer characteristics. The contribution model to characterize the apparent bending modulus in major and minor strength directions demonstrated good agreement with the test results. Based on this model interpreted by three-dimensional figures, the contribution variation characteristics in the major and minor strength directions were revealed.
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Free
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Assessing the Seismic Performance of Screws Used in Timber Structures by Means of Cyclic Bending Tests

https://research.thinkwood.com/en/permalink/catalogue1946
Year of Publication
2018
Topic
Connections
Seismic
Application
Walls
Floors
Author
Izzi, Matteo
Polastri, Andrea
Nebiolo, Flavio
Luzzani, Chiara
Year of Publication
2018
Format
Conference Paper
Application
Walls
Floors
Topic
Connections
Seismic
Keywords
Screws
Bending Tests
Ductility
Monotonic Tests
Reverse Cyclic Test
Seismic Performance
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 20-23, 2018, Seoul, Republic of Korea
Summary
The low-cycle seismic performance of typical screws used in timber structures is analysed by performing monotonic and fully reversed cyclic bending tests on the threaded length of the shank. Tests considered partially threaded screws made of carbon steel with diameter varying between 6 and 10 mm. Results of the monotonic bending tests are used to assess the compliance of the screws with the requirement of ductility prescribed by EN 14592 and to define the average yielding moment of the shank. Cyclic bending tests are carried out afterwards by assuming three classes of low cycle seismic performance (S1 - low ductility class, S2 - medium ductility class and S3 - high ductility class). Results of the cyclic tests are used to evaluate the residual moment of the shank, which is then compared to the average yielding moment from monotonic tests. The outcomes of the testing programmes highlight that screws with a diameter equal to 6 mm can be assigned to a low-cycle seismic class S2, while screws with a diameter greater than or equal to 8 mm are capable of ensuring a higher seismic performance and can be assigned to a seismic class S3.
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166 records – page 1 of 17.