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17 records – page 1 of 2.

Accurate Strength Parameters for Fasteners with Examples for Ring Shank Nails

https://research.thinkwood.com/en/permalink/catalogue1510
Year of Publication
2016
Topic
Connections
Mechanical Properties
Material
LVL (Laminated Veneer Lumber)
Author
Munch-Andersen, Jørgen
Svensson, Staffan
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
LVL (Laminated Veneer Lumber)
Topic
Connections
Mechanical Properties
Keywords
Withdrawal Test
Ring Shank Nails
Fasteners
Strength
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 344-352
Summary
Strength parameters for fasteners determined in accordance with the methods prescribed for the European CE-marking leads to quite different values for seemingly similar products from different manufactures. The results are hardly repeatable, to some extent due to difficulties in selecting representative timber samples for the testing. Beside this uncertainty, the declared values available to the designer concerns only structural timber, so no strength parameters are available for common engineered wood products such as LVL or plywood
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Analytical Modeling of Lateral Strength and Stiffness of Inclined Self-Tapping Screw Connection

https://research.thinkwood.com/en/permalink/catalogue2651
Topic
Mechanical Properties
Connections
Author
Zhao, Ruihan
Organization
University of Alberta
Country of Publication
Canada
Topic
Mechanical Properties
Connections
Keywords
Self-Tapping Screws
Lateral Strength
Lateral Stiffness
Withdrawal
Yield
Embedment
Research Status
In Progress
Summary
The objective of this research is to develop models for predicting lateral strength and stiffness of connections containing inclined self-tapping screws, by considering the contribution of the withdrawal and yield properties of the screws and embedment properties of the connecting members.
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Bond Behavior of Glued-In Timber Joint with Deformed Bar Epoxied in Glulam

https://research.thinkwood.com/en/permalink/catalogue537
Year of Publication
2014
Topic
Connections
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Author
Ling, Zhibin
Liu, Weiqing
Yang, Huifeng
Lu, Weidong
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Topic
Connections
Mechanical Properties
Keywords
Glued-in Rods
Bond behavior
Withdrawal Strength
Pull-Pull tests
Failure Modes
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
This paper describes the test program of glued-in deformed bar timber joint conducted in pull-pull configuration, which aims to investigate the bond behavior of glued-in deformed bar systems in glulam. The varying parameter are bar slenderness ratio and glue-line thickness. In order to obtain the bond stress distribution along the anchorage length, special deformed bar with strain gauges attached internally were designed. Test results show that both the bar slenderness ratio and glue-line thickness have obvious influence on withdrawal strength and bond behavior of glued-in deformed bar joint. Failure modes of specimens are also analyzed in this paper. Ductile failure modes of glued-in rod timber joint could be realized with reasonable design.
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Chapter 6: Fire Damage of Wood Structures

https://research.thinkwood.com/en/permalink/catalogue897
Year of Publication
2012
Topic
Fire
Mechanical Properties
Material
Solid-sawn Heavy Timber
LSL (Laminated Strand Lumber)
LVL (Laminated Veneer Lumber)
Author
Kukay, Brian
White, Robert
Woeste, Frank
Publisher
International Code Council
Year of Publication
2012
Country of Publication
United States
Format
Book/Guide
Material
Solid-sawn Heavy Timber
LSL (Laminated Strand Lumber)
LVL (Laminated Veneer Lumber)
Topic
Fire
Mechanical Properties
Keywords
Bending Tests
Withdrawal Tests
Load Bearing Capacity
Charring
Reduced Cross Section Method
Language
English
Research Status
Complete
Series
Inspection, Testing, and Monitoring of Buildings and Bridges
Summary
Depending on the severity, fire damage can compromise the structural integrity of wood structures such as buildings or residences. Fire damage of wood structures can incorporate several models that address (1) the type, cause, and spread of the fire, (2) the thermal gradients and fire-resistance ratings, and (3) the residual load capacity. The investigator should employ engineering judgment to identify those in-service members that are to be replaced, repaired, or can remain in-service as they are. Suchjudgment will likely be based on the visual inspection of damaged members, connections, and any protective membranes.
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Design Equations for Dowel Embedment Strength and Withdrawal Resistance for Threaded Fasteners in CLT

https://research.thinkwood.com/en/permalink/catalogue226
Year of Publication
2014
Topic
Connections
Material
CLT (Cross-Laminated Timber)
Author
Kennedy, Shawn
Salenikovich, Alexander
Munoz, Williams
Mohammad, Mohammad
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Topic
Connections
Keywords
Embedment Strength
Threaded Fasteners
withdrawal resistance
Lag Screws
Self Drilling Screws
Canada
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
The Canadian standard for engineering design in wood (CSA O86) adopted the European yield model for calculations of the lateral resistance of connections with dowel-type fasteners. This model takes into account the yielding resistance of the fastener, the assembly's geometry and the embedment strength of wood. The latter is considered a function of the relative density of wood and diameter of the fastener. The purpose of this study is to verify the significance of these variables as applied to the embedment strength for threaded dowel-type fasteners of diameters 6.4 mm and greater in Canadian glulam products. The importance of this research is justified by the growing interest in the use of large-diameter threaded fasteners in heavy timber and hybrid structures of high load-bearing capacity. Based on the results of 960 tests, a new design model for the embedment strength is proposed for potential implementation in CSA O86 standard and the impact of such a change is presented.
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Evaluation of Bending Performance of Nail Laminated and Dowel Laminated Timber

https://research.thinkwood.com/en/permalink/catalogue2309
Year of Publication
2019
Topic
Design and Systems
Mechanical Properties
Material
NLT (Nail-Laminated Timber)
DLT (Dowel Laminated Timber)
Application
Floors
Walls
Roofs
Bridges and Spans
Wood Building Systems

Experimental Investigations of Shear Connections with Self-Tapping-Screws for Cross-Laminated-Timber Panels

https://research.thinkwood.com/en/permalink/catalogue2295
Year of Publication
2019
Topic
Design and Systems
Connections
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems

Group Action of Axially-Loaded Screws in the Narrow Face of Cross Laminated Timber

https://research.thinkwood.com/en/permalink/catalogue1496
Year of Publication
2016
Topic
Mechanical Properties
Connections
Material
CLT (Cross-Laminated Timber)
Author
Brandner, Reinhard
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Topic
Mechanical Properties
Connections
Keywords
Axially-Loaded
Self-Tapping Screws
Withdrawal Properties
Stochastic Approach
Load-Displacement Curves
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 209-218
Summary
Withdrawal properties of axially-loaded groups of screws in the narrow face of cross laminated timber (CLT) are investigated by means of a stochastic approach based on a single screw model which provides a complete stochastic description of the load-displacement curve. Different group dimensions and configurations are analysed, featuring screws with equal or different thread-fibre angles. The stochastic approach is successfully verified by tests. Influences caused by shortcomings in assembling and by screws penetrating knots as well as gaps are addressed. Suggestions, relevant for the development of CLT system connectors and for practical applications, are made.
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Influence of Moisture Content and Gaps on the Withdrawal Resistance of Self Tapping Screws in CLT

https://research.thinkwood.com/en/permalink/catalogue299
Year of Publication
2014
Topic
Connections
Mechanical Properties
Moisture
Material
CLT (Cross-Laminated Timber)
Author
Silva, Catarina
Ringhofer, Andreas
Branco, Jorge
Lourenço, Paulo
Schickhofer, Gerhard
Organization
National Congress of Experimental Mechanics
Year of Publication
2014
Country of Publication
Portugal
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Topic
Connections
Mechanical Properties
Moisture
Keywords
Self-Tapping Screws
Withdrawal
Gaps
Moisture Content
Language
English
Conference
9th National Congress of Experimental Mechanics
Research Status
Complete
Notes
October 15-17, 2014, Aveiro, Portugal
Summary
Self-tapping screws (STS) have been proclaimed as the easiest solution for structural timber connections, in special for cross laminated timber (CLT) constructions. In order to understand deeply the composite model “CLT-STS”, an experimental campaign which comprised 270 withdrawal tests was carried out. Maximum withdrawal load capacity of self-tapping screws inserted in plane side of a three layered CLT panel was evaluated considering three main parameters: moisture levels of CLT (i), number of gaps (ii) and the width of gaps (iii). Regarding (i), connections were tested with CLT at 8%, 12% and 18% of moisture content. Concerning (ii) and (iii), different test configurations with 1, 2 and 3 gaps, with 0 or 4mm, were tested. The influences of moisture content and number of gaps were modeled. Further a correlation between test results and a prediction model developed by Uibel and Blaß (2007) has been proposed.
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The Influences of Moisture Content Variation, Number and Width of Gaps on the Withdrawal Resistance of Self Tapping Screws inserted in Cross Laminated Timber

https://research.thinkwood.com/en/permalink/catalogue1359
Year of Publication
2016
Topic
Connections
Moisture
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Silva, Catarina
Branco, Jorge
Ringhofer, Andreas
Lourenço, Paulo
Schickhofer, Gerhard
Publisher
ScienceDirect
Year of Publication
2016
Country of Publication
Netherlands
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Connections
Moisture
Mechanical Properties
Keywords
Withdrawal Tests
Withdrawal Resistance
Self-Tapping Screws
Moisture Content
Gaps
Language
English
Research Status
Complete
Series
Construction and Building Materials
Summary
A large experimental campaign comprised of 470 withdrawal tests was carried out, aiming to quantify the withdrawal resistance of self-tapping screws (STS) inserted in the side face of cross laminated timber (CLT) elements. In order to deeply understand the “CLT-STS” composite model, the experimental tests considered two main parameters: (i) simple and cyclic changes on moisture content (MC) and (ii) number and width of gaps. Regarding (i), three individual groups of test specimens were stabilized with 8%, 12% and 18% of moisture content and one group was submitted to a six month RH cycle (between 30% and 90% RH). Concerning (ii), different test configurations with 0 (REF), 1, 2 and 3 gaps, and widths equal to 0mm (GAP0) or 4mm (GAP4), were tested. The influences of MC and number of gaps were modeled by means of least square method. Moreover, a revision of a prediction model developed by Uibel and Blaß (2007) was proposed. The main findings of the experimental campaign were: the decrease of withdrawal resistance for specimens tested with MC=18% in most configurations; the unexpected increase of withdrawal resistance as the number of gaps with 0mm increased; and, the surprising increase of withdrawal resistance for REF specimens submitted to the RH cycle.
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17 records – page 1 of 2.