Shear behaviour of bond lines in glued laminated timber beams at high temperatures

Frangi, Andréa; Fontana, Mario; Mischler, Adrian

doi:10.1007/s00226-004-0223-y

Cited by 75 publications

(43 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The interaction between wood and adhesive should be studied, especially when the bonded wood products are exposed to large temperature changes. For example, the performance of bondlines at elevated temperatures has been reported (Clauss et al 2011;Falkner and Teutsch 2006;Frangi et al 2004). Clauss et al (2011) found that there were problems at high temperatures with some adhesives.…”

Section: Introductionmentioning

confidence: 99%

Impact of cold temperatures on the shear strength of Norway spruce joints glued with different adhesives

Wang

Hagman

Sundqvist³

et al. 2015

Eur. J. Wood Prod.

View full text Add to dashboard Cite

As wood construction increasingly uses engineered wood products worldwide, concerns arise about the integrity of the wood and adhesives used. Bondline strength is a crucial issue for engineered wood applications, especially in cold climates. In this study, Norway spruce (Picea abies) joints (150 mm 9 20 mm 9 10 mm) were bonded with seven commercially available adhesives: polyurethane (PUR), polyvinyl acetate (PVAc), emulsion-polymer-isocyanate (EPI), melamine-formaldehyde (MF), phenol-resorcinol-formaldehyde (PRF), melamine-urea-formaldehyde1 (MUF1), and melamine-urea-formaldehyde2 (MUF2). Each adhesive was tested at six temperatures: 20, -20, -30, -40, -50 and -60°C. Generally, within the temperature test range, temperature changes significantly affected the shear strength of solid wood and wood joints. As the temperature decreased, the shear strength decreased. PUR adhesive in most cases resulted in the strongest shear strength and MUF adhesive resulted in the weakest. MF and PRF adhesives responded to temperature changes in a similar manner to that of the PUR adhesive. The shear strengths of wood joints with PVAc and EPI adhesives were more sensitive to temperature change. At low temperatures, the variability of shear strengths increased with all adhesives. Percent wood failures of joints bonded with different adhesives in most cases were not sensitive to temperature changes.

show abstract

Section: Introductionmentioning

confidence: 99%

Impact of cold temperatures on the shear strength of Norway spruce joints glued with different adhesives

Wang

Hagman

Sundqvist³

et al. 2015

Eur. J. Wood Prod.

View full text Add to dashboard Cite

show abstract

“…It is well known that oven tests tend to give higher strength values in comparison to fire tests due to the influence of loading [16,24]. Further, change in wood moisture and the fact that the states of moisture and temperature in the fire situation are transient and not stationary as usual in the oven tests play an important role.…”

Section: Experimental Analysismentioning

confidence: 99%

“…The results of a series of oven tests carried out by Frangi et al [16] to study the shear behavior of different adhesives at elevated temperature demonstrated that the behavior of PUR adhesives strongly depends on the type of adhesive. More recently, further investigation on the influence of temperature on the shear strength of glued wood joints showed large differences in thermal resistance and fracture behavior between the adhesive systems tested [17].…”

Section: Introductionmentioning

confidence: 99%

Influence of the Adhesive on the Load-Carrying Capacity of Glued Laminated Timber Members in Fire

Klippel¹,

Frangi²,

Fontana³

2011

Fire Saf. Sci.

View full text Add to dashboard Cite

Design models for timber structures in fire usually take into account the loss in cross-section due to charring and the temperature-dependent reduction in strength of timber. For bonded timber elements like glued laminated timber beams it is assumed that the adhesive used does not influence the resistance of structural timber beams significantly. To investigate the fire resistance of bonded timber elements a comprehensive research project is currently in progress at the Institute of Structural Engineering of ETH Zurich, Switzerland. The aim of this research project is the development of a simplified design model for the fire resistance of bonded structural timber elements taking into account the behavior at elevated temperature of the adhesive used. This paper presents experimental analyses and results of first calculations performed on the influence of the adhesive on the load-carrying capacity of glued laminated timber members in fire. It is shown that the temperature-dependent material properties of the adhesive used in the bondline of glued laminated timber beams have small influence on the shear resistance. For the investigated timber beams failure occurs mainly due to exceeding the bending moment resistance. Because of the steep temperature gradient in timber beams during fire exposure the temperature in the inner region of the cross-section is rather low; hence the shear capacity in the bondline between the different lamellas is still sufficient. However, in case of finger jointed lamellas of glued laminated timber beams, the influence of adhesive used in the finger joints is more significant and has to be considered. Tensile tests at elevated temperatures on finger jointed specimens confirmed the significant influence of the adhesive used.

show abstract

“…In these cases, the design needs to compensate for differential movement of the components while still preserving structural integrity. The performance of glue lines at elevated temperatures is well documented (Frangi et al 2004;Falkner and Teutsch 2006;Clauss et al 2011). However, not much information is available on the stability of glue lines at low temperatures, especially extremely cold temperatures, although some studies of timber bridges in cold climates have been reported (Kainz and Ritter 1998;Wacker 2003Wacker , 2009.…”

Section: Introductionmentioning

confidence: 99%

Effect of Low Temperatures on the Block Shear Strength of Norway Spruce Glulam Joints

Wang¹,

Björnberg²,

Hagman³

et al. 2016

BioResources

View full text Add to dashboard Cite

The block shear strength of Norway spruce (Picea abies (L.) Karst.) glulam joints was tested under low temperatures. Glulam samples were glued with the three of the most common outdoor structural adhesives. The cold temperatures tested were 20, −20, −30, −40, −50, and −60 °C. Within the temperature test range, the block shear strength of the glulam joints was resistant to the effect of temperature. As the temperature decreased, the joints' block shear strength did not show any significant change. In most cases, phenol-resorcinol-formaldehyde (PRF) adhesive yielded the strongest block shear strength, while melamine-formaldehyde (MF) adhesive yielded the weakest block shear strength. Melamine-ureaformaldehyde (MUF) adhesive yielded similar results to those of MF adhesives for all temperatures tested. The block shear strengths of the glulam joints with PRF, MUF, and MF adhesives were not sensitive to temperature change. The results indicated that PRF, MUF, and MF adhesives are stable for outdoor structural engineered wood construction in cold climates. The results also suggest that the SS-EN 14080 (2013) standard for the block shear method may not be the proper standard for testing differences in shear strength at different temperatures. The EN 302-1 (2011) standard could be more suitable for this purpose.

show abstract

Shear behaviour of bond lines in glued laminated timber beams at high temperatures

Cited by 75 publications

References 4 publications

Impact of cold temperatures on the shear strength of Norway spruce joints glued with different adhesives

Impact of cold temperatures on the shear strength of Norway spruce joints glued with different adhesives

Influence of the Adhesive on the Load-Carrying Capacity of Glued Laminated Timber Members in Fire

Effect of Low Temperatures on the Block Shear Strength of Norway Spruce Glulam Joints

Contact Info

Product

Resources

About