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7 records – page 1 of 1.

Calculating the Fire Resistance of Wood Members and Assemblies: Technical Report No. 10

https://research.thinkwood.com/en/permalink/catalogue2492
Year of Publication
2020
Topic
Fire
Design and Systems
Material
CLT (Cross-Laminated Timber)
Application
Columns
Beams
Floors
Walls
Wood Building Systems
Decking

Concealed Spaces in Mass Timber and Heavy Timber Structures

https://research.thinkwood.com/en/permalink/catalogue2920
Year of Publication
2021
Topic
Fire
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
NLT (Nail-Laminated Timber)
Application
Floors
Decking
Walls
Roofs
Author
McLain, Richard
Organization
WoodWorks
Year of Publication
2021
Format
Report
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
NLT (Nail-Laminated Timber)
Application
Floors
Decking
Walls
Roofs
Topic
Fire
Keywords
IBC
Concealed Spaces
Dropped Ceiling
Sprinklers
Noncombustible Insulation
Research Status
Complete
Summary
Concealed spaces, such as those created by a dropped ceiling in a floor/ceiling assembly or by a stud wall assembly, have unique requirements in the International Building Code (IBC) to address the potential of fire spread in nonvisible areas of a building. Section 718 of the 2018 IBC includes prescriptive requirements for protection and/or compartmentalization of concealed spaces through the use of draft stopping, fire blocking, sprinklers and other means.
Online Access
Free
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Evaluating Timoshenko Method for Analyzing CLT under Out-of-Plane Loading

https://research.thinkwood.com/en/permalink/catalogue2836
Year of Publication
2020
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Ceilings
Decking
Floors
Walls
Author
Rahman, MD Tanvir
Ashraf, Mahmum
Ghabraie, Kazem
Subhani, Mahbube
Organization
Deakin University
Publisher
MDPI
Year of Publication
2020
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Ceilings
Decking
Floors
Walls
Topic
Mechanical Properties
Keywords
Rolling Shear
Shear Deformation
Timoshenko Theory of Bending
Shear Stiffness
Finite Element Method (FEM)
Research Status
Complete
Series
Buildings
Summary
Cross-laminated timber (CLT) is an engineered wood product made up of layers of structurally graded timber, where subsequent layers are oriented orthogonally to each other. In CLT, the layers oriented in transverse direction, generally termed as cross-layer, are subjected to shear in radial–tangential plane, which is commonly known as rolling shear. As the shear modulus of cross-layers is significantly lower than that in other planes, CLT exhibits higher shear deformation under out-of-plane loading in contrast to other engineered wood products such as laminated veneer lumber (LVL) and glue laminated timber (GLT). Several analytical methods such as Timoshenko, modified gamma and shear analogy methods were proposed to account for this excessive shear deformation in CLT. This paper focuses on the effectiveness of Timoshenko method in hybrid CLT, in which hardwood cross-layers are used due to their higher rolling shear modulus. A comprehensive numerical study was conducted and obtained results were carefully analyzed for a range of hybrid combinations. It was observed that Timoshenko method could not accurately predict the shear response of CLTs with hardwood cross layers. Comprehensive parametric analysis was conducted to generate reliable numerical results, which were subsequently used to propose modified design equations for hybrid CLTs.
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Stress-laminated timber decks in bridges: Friction between lamellas, butt joints and pre-stressing system

https://research.thinkwood.com/en/permalink/catalogue2891
Year of Publication
2020
Application
Decking
Author
Massaro, Francesco Mirko
Malo, Kjell Arne
Organization
Norwegian University of Science and Technology
Publisher
Elsevier
Year of Publication
2020
Format
Journal Article
Application
Decking
Keywords
Stress Laminated
Timber Bridges
Butt-Joint
Stiffness
Friction
Pre-Stress
Research Status
Complete
Series
Engineering Structures
Summary
Stress-laminated timber (SLT) decks in bridges are popular structural systems in bridge engineering. SLT decks are made from parallel timber beams placed side by side and pre-stressed together by means of steel rods. SLT decks can be in any length by just using displaced butt joints. The paper presents results from friction experiments performed in both grain and transverse direction with different levels of pre-stress. Numerical simulations of these experiments in addition to comparisons to full-scale experiments of SLT decks presented in literature verified the numerical model approach. Furthermore, several alternative SLT deck configurations with different amounts of butt joints and pre-stressing rod locations were modelled to study their influence on the structural properties of SLT decks. Finally, some recommendations on design of SLT bridge decks are given.
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Free
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Structural Tests of Concrete Composite-Cross-Laminated Timber Floors

https://research.thinkwood.com/en/permalink/catalogue2830
Year of Publication
2017
Topic
Connections
Mechanical Properties
Serviceability
Material
CLT (Cross-Laminated Timber)
Timber-Concrete Composite
Application
Floors
Decking
Author
Higgins, Christopher
Barbosa, R. Andre
Blank, Curtis
Organization
Oregon State University
Publisher
Oregon State University
Year of Publication
2017
Format
Report
Material
CLT (Cross-Laminated Timber)
Timber-Concrete Composite
Application
Floors
Decking
Topic
Connections
Mechanical Properties
Serviceability
Keywords
Bending Behaviour
Shear Connection
Long-term Behaviour
TCC
Orthrotropic Plates
Research Status
Complete
Summary
Experimental tests of a composite concrete-cross-laminated timber (CLT) floor system were conducted. The floor system was constructed with 5-ply CLT panels (6.75 in. thick) made composite with a 2.25 in. thick reinforced concrete topping slab. Four series of tests were performed using different specimen configurations and laboratory testing methods. Tests included: (1) Comparative one-way bending tests (CB) to evaluate the performance of alternative shear connectors used to join the concrete slab to the CLT panel; (2) Orthotropic stiffness and strength tests (OS) to evaluate the elastic orthotropic stiffness of the deck system and provide strength results for weak-axis bending and negative moment strength; (3) Full-scale system performance tests (FS) of a continuous floor span to establish strength at realistic span lengths and the influence of continuity; and (4) Long-term deformation tests (LT) to investigate creep deflections of the composite concrete-CLT floor system considering positive and negative bending influences. Results include overall strength, elastic stiffness values, deformation capacity, slip deformations along the concrete-CLT interface, predicted neutral axis locations in the composite concrete-CLT systems, and connection deformations.
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Free
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Surface Burning Characteristics of Glulam Decking

https://research.thinkwood.com/en/permalink/catalogue385
Year of Publication
2014
Topic
Fire
Material
Glulam (Glue-Laminated Timber)
Application
Decking
Author
Dagenais, Christian
Organization
FPInnovations
Year of Publication
2014
Format
Report
Material
Glulam (Glue-Laminated Timber)
Application
Decking
Topic
Fire
Keywords
Flame Spread
Thermally Thick Solids
Research Status
Complete
Summary
The key objective of this study was to evaluate the surface burning characteristics (flame spread rating) of glued-laminated timber (glulam) decking in accordance with CAN/ULC S102 test method [1]. This is part of a test series aimed at evaluating the flame spread rating of mass timber components, such as cross-laminated timber (CLT) and structural somposite lumber (SCL). More specifically, this study is solely focused on mass timber assemblies that are thick enough to be treated theoretically as semi-infinite solids (thermally thick solids) as opposed to thermally-thin, which is typical of traditional combustible finish products. The tested specimen in this series meets the provisions related to "heavy timber construction", per paragraph 3.1.4.7 of Division B of the National Building Code of Canada.
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Free
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Thermophysical properties of balsa wood used as core of sandwich composite bridge decks exposed to external fire

https://research.thinkwood.com/en/permalink/catalogue3073
Year of Publication
2022
Topic
Fire
Application
Decking
Author
Vahedi, Niloufar
Tiago, Carlos
Vassilopoulos, Anastasios P.
Correia, João R.
Keller, Thomas
Organization
École Polytechnique Fédérale de Lausanne (EPFL)
Universidade de Lisboa
Publisher
Elsevier
Year of Publication
2022
Format
Journal Article
Application
Decking
Topic
Fire
Keywords
Balsa Wood
Effective Thermophysical Properties
Thermal Conductivity
Specific Heat Capacity
Coefficient of Thermal Expansion
Charring Temperature
Charring Rate
Research Status
Complete
Series
Construction and Building Materials
Summary
The load-bearing performance of sandwich bridge decks comprising a balsa core and fiber-reinforced polymer composite face sheets exposed to fire is a main concern regarding the application of these deck systems. In order to obtain the thermal responses of the balsa core exposed to fire, the temperature-dependent values of thermal conductivity and specific heat capacity are required. Furthermore, information about the char depth and charring rate and the temperature-dependent coefficient of thermal expansion is also needed for the subsequent thermomechanical modeling. In the current study, the effective thermal conductivity and specific heat capacity of balsa up to 850 °C were obtained from one-dimensional transient heat transfer models and experimental data using an inverse heat transfer analysis. The results showed that both properties depend significantly on the stages of combustion, direction of heat flow (in the tracheid or transverse direction) and density. Moreover, charring temperatures and rates were obtained, again as a function of direction and density. Finally, the coefficient of thermal expansion was measured in the transverse direction during evaporation and pyrolysis.
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Free
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7 records – page 1 of 1.