Skip header and navigation

13 records – page 1 of 2.

An Experimental and Analytical Study on the Bending Performance of CFRP-Reinforced Glulam Beams

https://research.thinkwood.com/en/permalink/catalogue2972
Year of Publication
2022
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
He, Minjuan
Wang, Yuxuan
Li, Zheng
Zhou, Lina
Tong, Yichang
Sun, Xiaofeng
Organization
Tongji University
University of Victoria
Editor
Tam, Lik-ho
Publisher
Frontiers
Year of Publication
2022
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
CFRP Sheet
Four-point Bending Test
Numerical Model
Theoretical Analysis
Research Status
Complete
Series
Frontiers in Materials
Summary
The fiber-reinforced polymer is one kind of composite material made of synthetic fiber and resin, which has attracted research interests for the reinforcement of timber elements. In this study, 18 glued-laminated (glulam) beams, unreinforced or reinforced with internally embedded carbon fiber–reinforced polymer (CFRP) sheets, were tested under four-point bending loads. For the reinforced glulam beams, the influences of the strengthening ratio, the modulus of elasticity of the CFRP, and the CFRP arrangement on their bending performance were experimentally investigated. Subsequently, a finite element model developed was verified with the experimental results; furthermore, a general theoretical model considering the typical tensile failure mode was employed to predict the bending–resisting capacities of the reinforced glulam beams. It is found that the reinforced glulam beams are featured with relatively ductile bending failure, compared to the brittle tensile failure of the unreinforced ones. Besides, the compressive properties of the uppermost grain of the glulam can be fully utilized in the CFRP-reinforced beams. For the beams with a 0.040% strengthening ratio, the bending–resisting capacity and the maximum deflection can be enhanced approximately by 6.51 and 12.02%, respectively. The difference between the experimental results and the numerical results and that between the experimental results and analytical results are within 20 and 10%, respectively.
Online Access
Free
Resource Link
Less detail

Assessment and Optimisation of CFRP Reinforced Glulam Beams - A Feasibility Study in Design Stage Reinforcement Configurations for Pedestrian Bridge Applications

https://research.thinkwood.com/en/permalink/catalogue2458
Year of Publication
2019
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Bridges and Spans

Bamboo Reinforced Glulam Beams: An Alternative to CFRP Reinforced Glulam Beams

https://research.thinkwood.com/en/permalink/catalogue640
Year of Publication
2013
Topic
Design and Systems
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Echavarria, Cesar
Echavarría, Beatriz
Cañola, Hernán
Publisher
Scientific.net
Year of Publication
2013
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Design and Systems
Keywords
Bamboo
CFRP
Load-Deformation
Reinforcement
Stiffness
Strength
Research Status
Complete
Series
Advanced Materials Research
Summary
A research study was undertaken to investigate the mechanical performance of glulam beams reinforced by CFRP or bamboo. Local reinforcement is proposed in order to improve the flexural strength of glulam beams. The glulam beam is strengthened in tension and along its sides with the carbon fiber-reinforced polymer CFRP or bamboo. A series of CFRP reinforced glulam beams and bamboo reinforced glulam beams were tested to determine their load-deformation characteristics. Experimental work for evaluating the reinforcing technique is reported here. According to experiment results, the CFRP and bamboo reinforcements led to a higher glulam beam performance. By using CFRP and bamboo reinforcements several improvements in strength may be obtained.
Online Access
Free
Resource Link
Less detail

Bond Between Glulam and NSM CFRP Laminates

https://research.thinkwood.com/en/permalink/catalogue331
Year of Publication
2013
Topic
Design and Systems
Material
Glulam (Glue-Laminated Timber)
Author
Sena-Cruz, José
Jorge, Marco
Branco, Jorge
Cunha, Vitor
Publisher
ScienceDirect
Year of Publication
2013
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Topic
Design and Systems
Keywords
Carbon Fiber Reinforced Polymer
Pull-Out Tests
Bond behavior
Stress-Slip
Research Status
Complete
Series
Construction and Building Materials
Summary
With the aim of evaluating the bond behaviour between glulam and carbon fibre reinforced polymer laminates strips, an experimental program using pull-out tests was carried, when the near-surface strengthening technique is applied. Two main variables were studied: the bond length and the type of pull-out test configuration. The instrumentation included the loaded and free-end slips, as well as the pullout force. Based on the obtained experimental results, and applying an analytical-numerical strategy, the local bond stress-slip relationship was determined. In this work the tests are described, the obtained results are presented and analysed, and the applicability of an inverse analysis to obtain the local bond law is demonstrated.
Online Access
Free
Resource Link
Less detail

Evaluation of Delamination and Bending Performance of Composite CLT Reinforced with CFRP

https://research.thinkwood.com/en/permalink/catalogue2203
Year of Publication
2019
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Floors

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
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.
Online Access
Free
Resource Link
Less detail

High Performance CFRP-Timber-Concrete Laminated Composite Members

https://research.thinkwood.com/en/permalink/catalogue1698
Year of Publication
2016
Topic
Mechanical Properties
Material
Timber-Concrete Composite
Application
Beams
Author
Balogh, Jeno
Year of Publication
2016
Format
Conference Paper
Material
Timber-Concrete Composite
Application
Beams
Topic
Mechanical Properties
Keywords
Strength
Stiffness
Loading
Short-term
Laboratory Tests
Finite Element Model
Tension
CFRP
Failure Mode
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 4352-4359
Summary
This paper deals with laminated timber-concrete (LTC) composite beam members, for applications in sustainable building structures, in which the interlayer connection is achieved with adhesives, similarly to the glued laminated timber beams, instead of the classically used shear connectors (e.g. mechanical connectors or notches). Only a small number of studies of this type of high-performance members are available. The strength and stiffness of the LTC under short-term static ramp-loading were studied on new and retrofit (joist-type) floor members, through laboratory tests and non-linear finite element modelling. In the initial tests the typical failure mode observed was the failure of the wood in tension. Consequently, a carbon fibre reinforced polymer (CFRP) layer was added to the tension side of the timber layer, forming a multi-composite member. The research results indicate that the structural performance in terms of efficiencies and strength for the LTC beams exceeds the corresponding performance of similar classical timber-concrete beams with shear connectors due to the different shear transfer and failure modes. By adding the CFRP reinforcement to the tension fibres of the timber layer, the failure mode changed again, allowing for further increase in strength and stiffness.
Online Access
Free
Resource Link
Less detail

The Influence of CFRP Sheets on the Load-Bearing Capacity of the Glued Laminated Timber Beams under Bending Test

https://research.thinkwood.com/en/permalink/catalogue2900
Year of Publication
2021
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Sliwa-Wieczorek, Klaudia
Ostrowski, Krzysztof
Jaskowska-Lemanska, Justyna
Karolak, Anna
Organization
Cracow University of Technology
AGH University of Science and Technology
Wroclaw University of Science of Technology
Publisher
MDPI
Year of Publication
2021
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
CFRP
Load-Bearing Capacity
Bending Test
CT Analysis
Research Status
Complete
Series
Materials
Summary
Composite materials are increasingly used to strengthen existing structures or new load-bearing elements, also made of timber. In this paper, the effect of the number of layers of Carbon Fiber Reinforced Polymer (CFRP) on the load-bearing capacity and stiffness of Glued Laminated Timber beams was determined. Experimental research was performed on 32 elements—a series of eight unreinforced beams, and three series of eight reinforced beams: with one, three and five layers of laminate each. The beams with a cross-section of 38 mm × 80 mm and a length of 750 mm were subjected to the four-point bending test according to standard procedure. For each series, destructive force, deflection, mode of failure, and equivalent stiffness were determined. In addition, for the selected samples, X-ray computed tomography was performed before and after their destruction to define the quality of the interface between wood and composite. The results of the conducted tests and analyses showed that there was no clear relationship between the number of reinforcement layers and the load-bearing capacity of the beams and their stiffness. Unreinforced beams failed due to tension, while reinforced CFRP beams failed due to shear. Despite this, a higher energy of failure of composite-reinforced elements was demonstrated in relation to the reference beams.
Online Access
Free
Resource Link
Less detail

Numerical Modelling of Glulam Beams Externally Reinforced with CFRP Plates

https://research.thinkwood.com/en/permalink/catalogue1624
Year of Publication
2016
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Glišovic, Ivan
Pavlovic, Marko
Stevanovic, Boško
Todorovic, Marija
Year of Publication
2016
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
Bending Behaviour
CFRP
Finite Element Model
Load Deflection
Stiffness
Load Carrying Capacity
Strain
Reinforcement
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 2634-2641
Summary
Timber beams can effectively be reinforced using externally bonded fibre reinforced polymer (FRP) composites. This paper describes a nonlinear 3-dimensional finite element model which was developed in order to accurately simulate the bending behaviour of unreinforced and carbon FRP plate reinforced glulam beams. The model incorporates suitable constitutive relationship for each material and utilises anisotropic plasticity theory for timber in compression. Failure of beams was modelled based on the maximum stress criterion. The results of the finite element analysis showed a good agreement with experimental findings for load-deflection behaviour, stiffness, ultimate load carrying capacity and strain profile distribution of unreinforced and reinforced beams. The proposed model can be used to examine the effect of different geometries or materials on the mechanical performance of reinforced system.
Online Access
Free
Resource Link
Less detail

Performance of Glue-Laminated Beams from Malaysian Dark Red Meranti Timber

https://research.thinkwood.com/en/permalink/catalogue1822
Year of Publication
2018
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Ong, Chee Beng
Organization
University of Bath
Year of Publication
2018
Format
Thesis
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
Malaysian Dark Red Meranti (DRM)
Production
Phenol-Resorcinol Formaldehyde
Fabrication
Bonding Performance
Carbon Fiber Reinforced Polymer
Tension Face
Unreinforced
Fire Test
Failure
Finger Joints
Softwood
Europe
Density
End Pressure
Cramping Pressure
Strength
Charring Rate
Fire Performance
Polyurethane
Bending Strength
Research Status
Complete
Summary
In this study, Malaysian Dark Red Meranti (DRM) was used to manufacture glulam beams, following closely the requirements of BS EN 14080:2013 so as to emulate commercial production. Phenol resorcinol formaldehyde (PRF), commonly used in structural glulam production, was used in the fabrication of finger joints and laminations of the glulam beams. Factors influencing the mechanical properties of finger joints and bonding performance of laminations were investigated. Full size glulam beams were manufactured and tested in bending with partial and complete carbon fibre reinforced polymer (CFRP) reinforcement on the tension face and compared with the performance of unreinforced beams. A bench-scale fire test was proposed to describe the behaviour of DRM finger joints in tension under fire condition, in order to simulate the failure of finger joints on the tension side of a glulam beam in a standard fire test. Overall, DRM finger joints exhibited better bending strength than Spruce finger joints which represented softwood used in European glulam. Wood density and end pressure were shown to affect the strength properties of the finger joints. Higher cramping pressure was needed to produce DRM laminations with higher shear strength. The glulam beam with CFRP reinforcement had a higher bending strength than the unreinforced glulam beams but partial reinforcement had an adverse effect on beam strength. In the bench-scale fire test, DRM finger-jointed specimens exhibited lower charring rate than Spruce. Furthermore, PRF finger-jointed specimens showed better fire performance than finger-jointed specimens bonded with polyurethane (PUR) adhesive. In conclusion, it is hoped that results from this research will motivate engineers and architects in Malaysia to design and build structures from less-utilised local timber, specifically in the form of glulam, encouraging the timber industry in Malaysia to produce them commercially.
Online Access
Free
Resource Link
Less detail

13 records – page 1 of 2.