Skip header and navigation

4 records – page 1 of 1.

Effect of End Support Conditions on the Vibrational Performance of Cross-Laminated Timber Floors

https://research.thinkwood.com/en/permalink/catalogue209
Year of Publication
2014
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
Application
Floors
Author
Maldonado, Saul
Chui, Ying Hei
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Floors
Topic
Acoustics and Vibration
Keywords
End Support
Natural Frequency
Damping
Static Deflection
Finite Element Model
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
This study focuses on the vibrational behaviour of 3, 5 and 7-layer cross-laminated timber (CLT) plates supported on two sides with different support conditions. Three end support setups are proposed; 1) top load over the two supported edges, 2) direct fastening to support using self-tapping screws, 3) steel angle bracket support. The measured response parameters are natural frequencies, damping, and static deflection under a point load. The rotational stiffness with load, screws and steel angle brackets will be characterized through static tests. In addition, the effect of the span is studied by varying the test span and repeating the vibration and deflection tests. The laboratory tests will be supplemented with analytical modelling. The expected outcome is the development of approaches to more accurately calculate the natural frequency and static deflection under a point load, which can account for the influence of common support conditions encountered in service.
Online Access
Free
Resource Link
Less detail

In-Situ Testing at Wood Innovation and Design Centre: Floor Vibration, Building Vibration, and Sound Insulation Performance

https://research.thinkwood.com/en/permalink/catalogue284
Year of Publication
2015
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
Application
Walls
Floors
Author
Hu, Lin
Pirvu, Ciprian
Ramzi, Redouane
Organization
FPInnovations
Year of Publication
2015
Country of Publication
Canada
Format
Report
Material
CLT (Cross-Laminated Timber)
Application
Walls
Floors
Topic
Acoustics and Vibration
Keywords
Natural Frequency
Damping Ratio
Static Deflection Testing
Vibration Performance
Sound Transmission
Language
English
Research Status
Complete
Summary
In order to address the lack of measured natural frequencies and damping ratios for wood and hybrid wood buildings, and lack of knowledge of vibration performance of innovative CLT floors and sound insulation performance of CLT walls and floors, FPInnovations conducted a series of performance testing at the Wood Innovation Design Centre (WIDC) in Prince George, BC in April 2014, during construction, and in May 2015, after building completion and during its occupation. This report describes the building, tested floor and wall assemblies, test methods, and summarizes the test results. The preliminary performance data provides critical feedback on the design of the building for resisting wind-induced vibration and on the floor vibration controlled design. The data can be further used to validate the calculation methods and tools/models of dynamic analysis.
Online Access
Free
Resource Link
Less detail

Static and Dynamic Properties of Retrofitted Timber Beams Using Glass Fiber Reinforced Polymers

https://research.thinkwood.com/en/permalink/catalogue797
Year of Publication
2016
Topic
Design and Systems
Mechanical Properties
Material
Solid-sawn Heavy Timber
Application
Beams
Author
Bru, David
Baeza, Francisco Javier
Varona, Francisco
García-Barba, Javier
Ivorra, Salvador
Publisher
Springer Netherlands
Year of Publication
2016
Country of Publication
Netherlands
Format
Journal Article
Material
Solid-sawn Heavy Timber
Application
Beams
Topic
Design and Systems
Mechanical Properties
Keywords
Damping Ratio
Ductility
Natural Frequency
Glass Fiber Reinforced Polymer
Pine
Reinforcement
Static Properties
Dynamic Properties
Modal Analysis
Four Point Bending Test
Bending Strength
Language
English
Research Status
Complete
Series
Materials and Structures
ISSN
1871-6873
Summary
A study on the static and dynamic properties of sawn timber beams reinforced with glass fiber-reinforced polymer (GFRP) is reported in this paper. The experimental program is focused on the behavior of unidirectional wooden slabs, and the main objective is to fulfill the service state limit upon vibrations using GFRP when an architectonical retrofitting project is necessary. Two different typologies of reinforcement were evaluated on pine wood beams: one applied the composite only on the lower side of the beams, while the other also covered half of the beams depth. For the dynamic characterization, the natural frequency, damping ratio, and dynamic elastic modulus were measured using two different techniques: experimental modal analysis upon the whole beams; and bandwidth method using smaller samples of the same material. The static characterization consisted on four point bending tests, where elastic modulus, bending strength and ductility were assessed. The lower composite had better ductility and bending strength. On the other hand, the U-shaped laminate showed higher stiffness but also at a higher material cost. However, it allowed some ductility, i.e. compressive plasticity, even in the presence of hidden knots. Both dynamic techniques gave similar results and were capable of measuring the structure stiffness, even if short samples were used. Finally, the changes on dynamic properties because of the GFRP did not jeopardize the dynamic performance of the reinforced timber beams.
Online Access
Free
Resource Link
Less detail

Vibration Properties of a Timber Floor Assessed in Laboratory and During Construction

https://research.thinkwood.com/en/permalink/catalogue488
Year of Publication
2015
Topic
Acoustics and Vibration
Material
CLT (Cross-Laminated Timber)
Application
Floors
Author
Jarnerö, Kirsi
Brandt, Anders
Olsson, Anders
Publisher
ScienceDirect
Year of Publication
2015
Country of Publication
Netherlands
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Floors
Topic
Acoustics and Vibration
Keywords
Damping Ratios
Eurocode
Mode shape
Natural Frequency
Prefabrication
Boundary Conditions
Language
English
Research Status
Complete
Series
Engineering Structures
Summary
In the present work the change in natural frequencies, damping and mode shapes of a prefabricated timber floor element have been investigated when it was integrated into a building structure. The timber floor element was first subjected to modal testing in laboratory with ungrounded and simply supported boundary conditions, and then in situ at different stages of building construction. The first five natural frequencies, damping ratios and mode shapes of the floor element and the entire floor were extracted and analysed. It may be concluded that the major change in natural frequencies occur as the floor element is coupled to the adjacent elements and when partitions are built in the studied room, the largest effect is on those modes of vibration that largely are constrained in their movement. The in situ conditions have a great influence on the damping, which depends on the damping characteristics of the supports, but also on the fact that the floor is integrated into the building and interacts with it. There is a slight increase of damping in the floor over the different construction stages and the damping values seem to decrease with ascending mode order.
Online Access
Free
Resource Link
Less detail