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60 records – page 1 of 6.

Behavior of Strengthened Timber Concrete Composite Under Axial Loads

https://research.thinkwood.com/en/permalink/catalogue2778
Year of Publication
2021
Topic
Mechanical Properties
Material
Timber-Concrete Composite
Author
El-Salakawy, Tarek
Gamal, Amr
Publisher
ScienceDirect
Year of Publication
2021
Format
Journal Article
Material
Timber-Concrete Composite
Topic
Mechanical Properties
Keywords
Axial Loading
Strengthening
Wire Mesh
Epoxy
Modulus of Elasticity
Failure Mode
Ductility
Post Failure Behavior
Language
English
Research Status
Complete
Series
Case Studies in Construction Materials
Summary
The research study focuses on different strengthening techniques for timber concrete composites (TCC) using different types of wire and wire mesh integrated with a layer of epoxy on a timber core embedded in concrete using experimental and analytical procedure. The impact of TCC on axial compression performance, modulus of elasticity, failure mode and post failure behavior and ductility were compared to reference concrete specimens. Different types of wire and wire mesh used in strengthening of the timber core, timber core size and reinforcement in the concrete cylinder were all parameters considered in this study. Timing of application of the epoxy on the wire strengthened timber core was very important. For structural applications, where the weight reduction and ductility as well as post failure endurance are essential, the development of this composite is recommended. The ratio of the ductility index to the weight is discussed. The light weight of the timber composite, and the increased ductility were noted in this study. An equation to estimate the axial compression capacity of the strengthened timber concrete composite was developed in this study. This study will pave the way for further applications for timber concrete composite aiming at reducing dead weight of concrete and the reducing the amount of concrete and steel in construction.
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Experimental Analysis of Passively and Actively Reinforced Glued-laminated Timber with Focus on Ductility

https://research.thinkwood.com/en/permalink/catalogue2823
Year of Publication
2021
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Livas, Charalampos
Ekevad, Mats
Öhman, Micael
Publisher
Taylor&Francis Online
Year of Publication
2021
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
Reinforcement
Ductility
Bending Test
Steel
Language
English
Research Status
Complete
Series
Wood Material Science & Engineering
Summary
When glued-laminated timber are subjected to bending moment, they usually fail in a brittle way in the tension zone before the compressive zone reaches the compressive strength of wood. This means that the compression strength of wood is not fully exploited. By reinforcing the tension zone, the failure mode of glued-laminated timber can be changed from tensile to compressive. As a result, by utilizing the higher compressive strength, reinforced glued-laminated timber become stronger and the failure mode becomes compressive and ductile. This paper presents experimental results of the effect of steel reinforcements in the tension zone of glued-laminated timber. Four passively reinforced beams, four actively reinforced beams, and seven unreinforced beams were tested to failure in four-point bending tests. The experimental results confirmed the brittle tension failure in the unreinforced beams as well as the ductile and compressive failure in the reinforced beams. Furthermore, the experiments revealed the increase of the passively and the actively reinforced glued-laminated timber relative to the reference beams for strengths (26% and 39%) and stiffnesses (30% and 11%). Ductilities were increased from 7.7% for the reference beams to 90% and 75% for the passively and the actively reinforced glued-laminated timber, respectively.
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Influence of Steel Properties on the Ductility of Doweled Timber Connections

https://research.thinkwood.com/en/permalink/catalogue2789
Year of Publication
2021
Topic
Connections
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
LVL (Laminated Veneer Lumber)
Author
Geiser, Martin
Bergmann, M.
Follesa, Maurizio
Publisher
ScienceDirect
Year of Publication
2021
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
LVL (Laminated Veneer Lumber)
Topic
Connections
Mechanical Properties
Keywords
Ductility
Strength
Monotonic Test
Cyclic Tests
Dowel Type Fastener
Serial Yielding
Doweled Connections
Capacity Design
Strain Hardening Ratio
Steel
Seismic
Language
English
Research Status
Complete
Series
Construction and Building Materials
Summary
In the seismic design of structures according to the dissipative structural behaviour, the connection ductility is crucial in order to ensure the desired level of energy dissipation of the overall structure. Therefore, in case of ductile zones composed of dowel-type fasteners arranged in series, it is important to ensure that all the fasteners can fully develop their energy dissipation capacity by plastic deformations. However, when different types of connections made of two symmetrical and serially arranged assemblies of dowel-type fasteners are tested, it often appears that only few fasteners fully work in the plastic region while most of the remaining ones exhibit very low yielding. Looking at the causes of this dysfunction, a possible explanation is due to the fact that the rules for the seismic design of dissipative zones in timber structures given in international codes and used in common practice often make reference only to the steel quality of the dowel-type fasteners specifying a minimum tensile strength or sometime, like is the case of the current version of Eurocode 8, only to maximum values of the dowel-type fastener diameter and of the thickness of the connected timber or wood-based members. Also, the research conducted so far about the ductile behaviour of serially arranged connections was not focused on the post-elastic properties of steel. However, for the seismic design of ductile zones of other materials, such as for example is the case of reinforced concrete walls, post-elastic characteristics of steel are required for the reinforcing bars, in order to achieve the desired dissipative behaviour. Inspired by this fact, timber connections composed of serially arranged dowels made of steel grades with different hardening ratio and elongation at maximum tensile stress were fabricated and tested. The purpose of this work is to understand if the use of steel with significant post-elastic properties may help to solve the problem of limited yielding in serially arranged dowel-type connections. The tested specimens were composed of two symmetrical timber members made of Glulam and LVL connected to two 6 mm thick slotted-in steel plates by means of 9 steel dowels with a diameter of 6.0 mm, which were subjected to monotonic and cyclic tests carried out by implementing dowels made of steel with favourable post-elastic properties. The results showed that the simultaneous yielding of two serially arranged dowelled assemblies is possible, although not fully. Moreover, assuming as reference the steel grade with the lowest post-elastic properties, the connection ductility and strength measured through monotonic and cyclic tests increased by about 30% for the steel grades with the highest hardening ratio and elongation at maximum tensile stress, whereas the displacement at maximum strength was about five times higher. In addition, it was found that confinement of the timber members and shaping of holes were crucial in order to avoid undesired and premature brittle failures and to increase the connection strength and ductility. The results obtained may be useful in order to bring a reassessment of the code requirements regarding the steel properties of ductile connections as well as of certain principles of dimensioning and detailing.
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Bending Capacity of Orthogonal and Parallel Glulam T-section Beams

https://research.thinkwood.com/en/permalink/catalogue2476
Year of Publication
2020
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Bridges and Spans
Author
Wang, Jiejun
Yang, Tao
Ning, Fan
Rao, Zhenyu
Publisher
Eastern Macedonia and Thrace Institute of Technology (EMaTTech)
Year of Publication
2020
Country of Publication
Greece
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Bridges and Spans
Topic
Mechanical Properties
Keywords
Bearing Capacity
Stiffness
Integrity
Strain
Deflection
Ultimate Bearing Capacity
Shear Strength
Finite Element Model
Displacement
Failure Mechanism
Ductility
Language
English
Research Status
Complete
Series
Journal of Engineering Science and Technology Review
ISSN
1791-2377
Online Access
Free
Resource Link
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Flexural Strengthening of Composite Bridge Glued Laminated Timber Beams-Concrete Plate Using CFRP Layers

https://research.thinkwood.com/en/permalink/catalogue2587
Year of Publication
2020
Topic
Design and Systems
Material
Glulam (Glue-Laminated Timber)
Application
Bridges and Spans
Author
Mujiman, M
Igustiany, F
Hakiki, R
Publisher
IOP Publishing Ltd
Year of Publication
2020
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Bridges and Spans
Topic
Design and Systems
Keywords
CFRP
Carbon Fiber Reinforced Polymer
Flexural Strength
Stiffness
Ductility
Reinforcement
Language
English
Research Status
Complete
Series
IOP Conference Series: Materials Science and Engineering
Summary
The timber bridge design although economical, often has difficulty producing enough rigidity so that a solution is needed to solve it. The use of CFRP (Carbon Fiber Reinforced Polymer) as a reinforcement of structural elements if properly designed and implemented can produce an effective and efficient composite structure. The experimental study aims to analyse the strength, stiffness and ductility of flexural strengthening composite bridge glued laminated timber beams-concrete plates using CFRP layers. The dimensions of the composite glued laminated timber beams 100/180 mm and concrete plate 75/300 mm with a length of 2,480 mm. The number of specimens is 3 composite glued laminated timber beams-concrete plate consisting of 1 test beam without CFRP reinforcement, 1 test beam with one layer CFRP reinforcement, and 1 test beam with three layer CFRP reinforcement. Experimental testing of flexural loads is done with two load points where each load is placed at 1/3 span length. The test results show that the strength of composite laminated timber beams glued - concrete plates BN; BL-1; BL-2 in a row 81.32; 82.82; 82.69 kN/mm; stiffness in a row 7.51; 8.22; 6.32 kN/mm and successive ductility of 16.67; 28.83; 20.21.
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Mechanical Experimental Study on Tensile Bolted Connections of Crosslaminated Timber

https://research.thinkwood.com/en/permalink/catalogue2450
Year of Publication
2020
Topic
Connections
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Walls
Floors
Author
Su, Chenxiao
Xiong, Haibei
Publisher
Tech Science Press
Year of Publication
2020
Country of Publication
United States
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Walls
Floors
Topic
Connections
Mechanical Properties
Keywords
Monotonic Loading
Cyclic Loading
Deformation
Failure Modes
Wall-to-Wall
Wall-to-Floor
Bolted Connection
Load-Slip
Bearing Capacity
Yielding Point
Stiffness
Ductility
Language
English
Research Status
Complete
Series
Structural Durability & Health Monitoring
Online Access
Free
Resource Link
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Connections for Stackable Heavy Timber Modules in Midrise to Tall Wood Buildings

https://research.thinkwood.com/en/permalink/catalogue2087
Year of Publication
2019
Topic
Connections
Design and Systems
Seismic
Material
LVL (Laminated Veneer Lumber)
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Zhang, Chao
Lee, George
Lam, Frank
Organization
University of British Columbia
Year of Publication
2019
Country of Publication
Canada
Format
Report
Material
LVL (Laminated Veneer Lumber)
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Connections
Design and Systems
Seismic
Keywords
Modular
Intra-module Connection
Inter-module Vertical Connection
Inter-module horizontal Connection
Mid-Rise
Tall Wood
Screws
Load Transfer
Steel Angle Bracket
Stiffness
Strength
Ductility
Language
English
Research Status
Complete
Summary
In Phase I (2018-19) of this project on Prefabricated Heavy Timber Modular Construction, three major types of connections used in a stackable modular building were studied: intramodule connection, inter-module vertical connection, and inter-module horizontal connection. The load requirement and major design criteria were identified...
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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

Failure Modes and Mechanical Properties of Bracket Anchor Connections for Cross-Laminated-Timber

https://research.thinkwood.com/en/permalink/catalogue2152
Year of Publication
2019
Topic
Connections
Mechanical Properties
Seismic
Material
CLT (Cross-Laminated Timber)

Study on Flexural Behavior of Cross-Laminated Timber Based on Different Tree Species

https://research.thinkwood.com/en/permalink/catalogue2215
Year of Publication
2019
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Lu, Weidong
Gu, Jiahui
Wang, Bibo
Publisher
Hindawi Publishing Corporation
Year of Publication
2019
Country of Publication
Egypt
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Mechanical Properties
Keywords
Flexural Behavior
Failure Modes
Stiffness
Ductility
Ultimate Bearing Capacity
Language
English
Research Status
Complete
Series
Advances in Materials Science and Engineering
Online Access
Free
Resource Link
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60 records – page 1 of 6.