Seismic design of a multi-story cross laminated timber building based on component level testing
https://www.researchgate.net/publication/274959602... [Seismic Performance] [Conference Paper] 2012
Shiling Pei, Marjan Popovski, John W. van de Lindt
Cross laminated timber (CLT) is a new type of timber structural system that has just been introduced in North America, but has been used successfully in Europe for over 20 years. There have not been any notable data sets developed on the performance of tall CLT buildings during major earthquakes and there are no seismic design criteria currently in place for CLT structures. Shake table testing of walls, assemblies and multi-storey CLT structures have been performed, and development of dedicated ...

Reinforcement of Dowel Type Timber Joints Using Cross-Laminated CFPR
http://repositum.tuwien.ac.at/obvutwoa/content/pag... [Mechanical Performance] [Conference Paper] 2016
Nobuyoshi Yamaguchi, Naoaki Shibata
Reinforcement of timber joints using Carbon fibres was conducted to improve those mechanical properties such as strengths and deformability. CFRP (Carbon Fibre Reinforced Polymer) was developed for the reinforcement of timber joints. The CFRP consists of laminated CF-sheets which were oriented in the parallel and cross directions. Single and double shear capacities of the dowel type timber joints reinforced with the CFRP were examined. The CFRP were glued on the timber, and the fasteners were in...

Force Transfer around Openings in Cross-Laminated Timber Shear Walls
http://ascelibrary.org.ezp1.lib.umn.edu/doi/abs/10... [Mechanical Performance] [Journal Article] 2017
Sai Ganesh S. Pai, Framk Lam, Terje Haukaas
This paper presents a study on force transfer around openings (FTAO) in cross-laminated timber (CLT) shear walls. To elucidate the load transfer mechanism in CLT walls, this study used finite-element models to study five different CLT shear wall configurations. The effect of uncertainty in the behavior of connectors in the wall over its force-deformation behavior and design transfer force was also studied. In a coupled-panel wall, the presence of an opening decreased the strength and stiffness o...

Multi-scale modelling of rolling shear failure in cross-laminated timber structures by homogenisation and cohesive zone models
https://ac.els-cdn.com/S0020768315004898/1-s2.0-S0... [Mechanical Performance] [Journal Article] 2016
E.I. Saavedra Flores, K. Saaverdra, J. Hinojosa, Y. Chandra, R. Das
In this paper we investigate the rolling shear failure in cross-laminated timber structures by homogenisation and cohesive zone models. In order to predict the structural response, four spatial scales are interlinked within a purely kinematic multi-scale modelling framework. The constitutive description has incorporated information coming from the wood cell-wall in the order of a few nanometres, wood fibres with dimensions of tens of micrometres and growth rings described by a few millimetres. T...

Determination of the elastic and stiffness characteristics of cross-laminated timber plates from flexural wave velocity measurements
https://ac.els-cdn.com/S0022460X17303243/1-s2.0-S0... [Vibration/Acoustic Performance] [Journal Article] 2017
Andrea Santoni, Stefan Schoenwald, Bart Van Damme, Patrizio Fausti
Cross-laminated timber (CLT) is an engineered wood with good structural properties and it is also economically competitive with the traditional building construction materials. However, due to its low volume density combined with its high stiffness, it does not provide sufficient sound insulation, thus it is necessary to develop specific acoustic treatments in order to increase the noise reduction performance. The materials mechanical properties are required as input data to perform the vibro-ac...

Variations in sound insulation in cross laminated timber housing construction
http://ltu.diva-portal.org/smash/get/diva2:1004267... [Vibration/Acoustic Performance] [Conference Paper] 2011
Rikard Oqvist, Fredrik Ljunggren, Anders Agren
If variations and uncertainty in building acoustic measurements can be controlled, construction costs can potentially be reduced since the building will not have to be; acoustically over-dimensioned. Field measurements of impact and airborne sound; insulation were carried out for an industrially prefabricated cross-laminated timber (CLT) system of plate elements. The results from 18 rooms, forming three groups with respect; to size, were compared to a similar study dealing with a volume based bu...

A trapeze edging method for cross laminated timber panel production
https://www.diva-portal.org/smash/get/diva2:100360... [General Information] [Journal Article] 2015
Magnus Fredricksson, Peter Bomark, Olof Broman, Anders Gronlund
Sawing thin logs results in lower volume yield than sawing thicker logs. This is due to the geometry of logs; fitting rectangular blocks inside an approximately cylindrical shape, i.e. boards into logs, is more difficult for small diameters than for large diameters. If logs were sawn in a way that follows the outer shape to a larger degree, yield could be increased, especially for small diameter logs. The hypothesis of this study was that this can be done in the edging operations of a sawmill, w...

Development and Evaluation of Mechanical Joints for Composite Floor Elements with Cross Laminated Timber
https://www.diva-portal.org/smash/get/diva2:990749... [Economics/Costs] [Thesis/Dissertation] 2015
Nicolas Jacquier
One of the important issues in the development of a multi-storey timber construction system is the definition of the floor solution. This thesis focuses on the development of composite floor solutions where Cross Laminated Timber (CLT) panels are used as a base element. Preliminary investigations on shear connections between prefabricated concrete beams and CLT panels were performed. The focus is on investigations on glulam-CLT composite beam elements, and the mechanical shear connectors used to...

How CLT Could Change the US Building Landscape
http://www.constructiondive.com/news/how-clt-could... [General Information] [Magazine/Newspaper Article] 2017
Mary Tyler March
Project teams looking for building materials and systems with a lower environmental impact are increasingly eyeing wood — specifically cross-laminated timber (CLT), a type of mass timber that, research has shown, rivals concrete and steel in performance but has a smaller environmental footprint. While CLT has been used in buildings across the globe, U.S. markets have been slower to adopt it for structural applications, especially in high-rise buildings. Already, CLT projects in the U.K., such a...

Forest Resources of the United States, 2012: A Technical Document Supporting the Forest Service Update of the 2010 RPA Assessment
https://www.srs.fs.usda.gov/pubs/gtr/gtr_wo091.pdf... [General Information] [Report] 2012
Sonja N. Oswalt, W. Brad Smith, Patrick D. Miles, Scott A. Pugh
Forest resource statistics from the 2010 Resources Planning Act (RPA) Assessment were updated to provide current information on the Nation’s forests as a baseline for the 2015 national assessment. Resource tables present estimates of forest area, volume, mortality, growth, removals, and timber products output in various ways, such as by ownership, region, or State. Current resource data and trends are analyzed and placed within the context of changes since 1953. Additional analyses look at the r...

A numerical study of couple timber walls with slip friction damping devices
http://www.sciencedirect.com/science/article/pii/S... [Seismic Performance] [Journal Article] 2016
Ashkan Hashemi, Reza Masoudnia, Pierre Quenneville
In rocking timber structures, the traditional connections such as nailplates may need to be replaced by damping devices to provide the required lateral resistance and dissipate the seismic energy. This study seeks to investigate the seismic behaviour of coupled timber walls with slip friction connections. Slip friction connections present a low damage solution as they do not suffer from stiffness degradation and can be used after a seismic event. The seismic response of the described system is c...

Mass Timber - The Next Generation of Wood Construction
http://www.woodworks.org/wp-content/uploads/17SE06... [General Information] [Presentation] 2017
Tom Williamson
This presentation provides an overview of two products at the heart of the modern mass timber revolution: glued-laminated timber (glulam) and cross-laminated timber (CLT). Advantages and unique design considerations associated with these products will be covered, including specification, code compliance, connections, fire resistance and structural design. Modern glulam and CLT applications in North America will be reviewed using project examples. The potential for expanded applications, includin...

Effects of Exposed Cross Laminated Timber on Compartment Fire Dynamics
https://ac.els-cdn.com/S0379711217301881/1-s2.0-S0... [Fire Performance] [Journal Article] 2017
Rory M. Hadden, Alistair I. Bartlett, Juan P. Hidalgo, Simon Santamaria, Felix Wiesner, Luke A. Bisby, Susan Deeny, Barbara Lane
A series of compartment fire experiments has been undertaken to evaluate the impact of combustible cross laminated timber linings on the compartment fire behaviour. Compartment heat release rates and temperatures are reported for three configuration of exposed timber surfaces. Auto-extinction of the compartment was observed in one case but this was not observed when the experiment was repeated under identical condition. This highlights the strong interaction between the exposed combustible mater...

Tests on Shear Connections in Prefabricated Composite Cross-Laminated-Timber and Concrete Elements
https://www.diva-portal.org/smash/get/diva2:100510... [Connectors] [Conference Paper] 2012
Nicolas Jacquier, Ulf Arne Girhammar
The authors report on an experimental test program on different shear connectors to be used in floor elements where prefabricated concrete beams are to be connected on top of cross-laminated timber (CLT) panels. The objective is to evaluate the level of composite action that can be achieved and the increase of strength and stiffness when combining effectively these structural components in a floor element. Shear tests were performed on 12 specimens in total. The shear connector consists of a ste...

Taller Wood Buildings Coming Soon
http://www.naiop.org/en/Magazine/2017/Spring-2017/... [Tall Buildings] [Magazine/Newspaper Article] 2017
Steve White
...

Elastic Properties of Full-Size Mass Timber Panels: Characterization Using Modal Testing and Comparison with Model Predictions
http://www.sciencedirect.com/science/article/pii/S... [Mechanical Performance] [Journal Article] 2017
Jaianhui Zhou, Ying Hei Chui, Meng Gong, Lin Hu
Mass timber panel products are leading the evolution of wood construction throughout the world. In-plane elastic properties of mass timber panels are critical in serviceability design, especially when two-dimensional mechanical behaviour is considered. In this study, the moduli of elasticity (MOE) in major and minor strength directions (Ex and Ey), and in-plane shear modulus (Gxy) of 51 industrial size cross laminated timber (CLT) panels, 4 multi-ply solid wood panels (MSWP) were measured by a m...

Effects of the Thickness of Cross-Laminated Timber (CLT) Panels Made from Irish Sitka Spruce on Mechanical Performance in Bending and Shear
http://www.sciencedirect.com/science/article/pii/S... [Raw Materials] [Journal Article] 2016
Karol Sikora, Daniel O. McPOlin, Annette M. Harte
An investigation was carried out on CLT panels made from Sitka spruce in order to establish the effect of the thickness of CLT panels on the bending stiffness and strength and the rolling shear. Bending and shear tests on 3-layer and 5-layer panels were performed with loading in the out-of-plane and in-plane directions. ‘Global’ stiffness measurements were found to correlate well with theoretical values. Based on the results, there was a general tendency that both the bending strength and rollin...

Design of Cross-Laminated Timber in Fire
https://www.tandfonline.com/doi/abs/10.2749/101686... [Fire Performance] [Journal Article] 2016
Michael Klippel,Joachim Schmid
Cross-laminated timber (CLT) is a popular engineered wood product for loadbearing wall, floor and roof elements to realise innovative and high-quality modern timber structures. The behaviour of CLT panels exposed to fire requires careful evaluation to allow the expansion of CLT elements usage in buildings. This paper first presents a new charring model for timber in general and CLT specifically, based on the results of numerous fire tests with CLT and the current fire design according to EN 1995...

Reliability analysis and duration-of-load strength adjustment factor of the rolling shear strength of cross laminated timber
https://link.springer.com/content/pdf/10.1007%2Fs1... [Mechanical Performance] [Journal Article] 2016
Yuuan Li, Frank Lam
In this study, the duration-of-load effect on the rolling shear strength of cross laminated timber (CLT), with different cross-sectional layups (five-layer and three-layer), was evaluated. A stress-based damage accumulation model is chosen to evaluate the duration-of-load strength adjustment factor of the rolling shear strength of CLT. This model incorporates the established short-term rolling shear strength of material and predicts the time to failure under arbitrary loading history. The model ...

Evaluation of glue line shear strength of laminated structures using block and core type spcimens
https://link.springer.com/content/pdf/10.1007%2Fs0... [Mechanical Performance] [Journal Article] 2017
Florindo Gaspar, Helena Cruz, Augusto Gomes
Monitoring and evaluation of glued laminated timber structures in service is essential to warrant its integrity, where non-destructive techniques play an important role. This paper describes the results obtained on glued laminated timber beams of maritime pine, with and without preservative treatment, and of spruce, exposed to natural outdoor environment as well as to artificial weathering. The assessment of glue lines’ shear strength was investigated through the extraction and testing of cores ...