Towards enhancing the post-peak performance of glued-laminated timber beams using multi-directional fibre reinforced polymers

2020 ◽  
Vol 215 ◽  
pp. 110680
Author(s):  
Daniel Lacroix ◽  
Ghasan Doudak
Keyword(s):  
Peak Performance ◽  
Reinforced Polymers ◽  
Glued Laminated Timber ◽  
Timber Beams

Study on the strength of glued laminated timber beams with round holes: difference in structural performance between homogeneous-grade and heterogeneous-grade timber

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Shigefumi Okamoto ◽  
Nobuhiko Akiyama ◽  
Yasuhiro Araki ◽  
Kenji Aoki ◽  
Masahiro Inayama
Keyword(s):  
Scots Pine ◽  
Maximum Shear Stress ◽  
Material Strength ◽  
Laminated Beams ◽  
Strength Grade ◽  
Glued Laminated Timber ◽  
The Difference ◽  
Materials Used ◽  
Beam Height ◽  
Timber Beams

AbstractVarious design codes and design proposals have been proposed for glued laminated timber beams with round holes, assuming that the entire beam is composed of homogeneous-grade timber. However, in Japan, glued laminated timber composed of homogeneous-grade timber is rarely used for beams. In this study, the difference in the load-bearing capacity of glued laminated beams composed of homogeneous-grade timber and heterogeneous-grade timber with round holes when fractured by cracking was investigated experimentally and analytically. The materials used in the tests were glued laminated beams composed of homogeneous-grade Scots pine timber with a strength grade of E105-F345 and heterogeneous-grade Scots pine timber with a strength grade of E105-F300. Experiments confirmed that although the glued laminated beams composed of heterogeneous-grade timber have a lower material strength in the lamina with holes, its resistance to fracturing due to cracks associated with the holes is almost the same as that of the glued laminated beams composed of homogeneous-grade timber. The stresses acting on the holes in the laminated timber with holes of less than half the beam height were lower in the glued laminated beams composed of heterogeneous-grade timber than in the glued laminated beams composed of homogeneous-grade timber. The ratio of the stresses was found to be approximately equal to the ratio of the maximum bending stress or the maximum shear stress acting on the inner layer lamina, as determined by Bernoulli–Euler theory.

Experimental investigation of glued-laminated timber beams with Vectran-FRP reinforcement

2020 ◽  
Vol 202 ◽  
pp. 109818 ◽  
Author(s):  
Bruno F. Donadon ◽  
Nilson T. Mascia ◽  
Ramon Vilela ◽  
Leandro M. Trautwein
Keyword(s):  
Experimental Investigation ◽  
Glued Laminated Timber ◽  
Frp Reinforcement ◽  
Timber Beams

Ductile Design of Glued-Laminated Timber Beams

2009 ◽  
Vol 14 (3) ◽  
pp. 113-122 ◽  
Author(s):  
Roberto Tomasi ◽  
Maria Adelaide Parisi ◽  
Maurizio Piazza
Keyword(s):  
Glued Laminated Timber ◽  
Timber Beams

Shear strength of spruce glued—laminated timber beams

1985 ◽  
Vol 12 (3) ◽  
pp. 661-672 ◽  
Author(s):  
F. J. Keenan ◽  
J. Kryla ◽  
B. Kyokong
Keyword(s):  
Shear Strength ◽  
Cross Sections ◽  
Weibull Model ◽  
Longitudinal Shear ◽  
Douglas Fir ◽  
Published Data ◽  
Cross Sectional ◽  
Characteristic Value ◽  
Glued Laminated Timber ◽  
Timber Beams

The effect of size on longitudinal shear strength has been well established for Douglas-fir glued–laminated (glulam) timber beams. The present study examined whether this phenomenon exists in glulam beams made of spruce. The experiment consisted of three projects in which beams of various sizes were tested under concentrated mid-span load. The project A beams had clear spruce webs and white elm flanges with cross-sectional dimensions varying from 25 × 25 mm to 75 × 75 mm. The project B beams had spruce glulam webs with Douglas-fir flanges; cross sections ranged from 20 × 100 mm to 90 × 200 mm. In project C, three groups of 10 replications of commercially representative sizes of glulam beams were made from stiffness-rated spruce–pine–fir lumber. The beam cross sections were 76 × 200 mm, 76 × 400 mm, and 127 × 400 mm.The results indicated that depth, width, and shear plane had significant effects on the longitudinal shear strength of the beams in project A. Depth, width, and shear span of the small glulam beams in project B also had highly significant effects on shear strength. However, no effects of depth and width on the shear strength of glulam beams in project C were found. Regression analysis showed no dependence of shear strength on sheared volume for the beams of all three projects. The three-parameter Weibull model also failed to predict the near-minimum shear strength of spruce glulam beams. The results suggested that the lower-bound shear strength of spruce glulam beams is a constant (regardless of beam volume) and could be used as a single characteristic value for glulam design in shear. Further review of published data indicates that this may also be the case for Douglas-fir glulam but with a lower characteristic value than for spruce.

Influences of Scarf-Joint of the Laminae in the Strength and Elasticity of Glued Laminated Timber Beams

2017 ◽  
Vol 864 ◽  
pp. 336-340 ◽  
Author(s):  
E.V.M. Carrasco ◽  
J.N.R. Mantilla ◽  
M.A. Smits ◽  
V.D. Pizzol ◽  
P.V. Krüger ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
Linear Regression ◽  
Modulus Of Elasticity ◽  
Effective Elastic Modulus ◽  
Araucaria Angustifolia ◽  
Timber Beam ◽  
Glued Laminated Timber ◽  
Scarf Joint ◽  
Timber Beams

The objective of this work is to determinate the influence of the scarf-jointed in the strength and the modulus of elasticity of the glued laminated timber beam. To determine this influence, several tests with the outer laminae with scarf-joint and the bevel with different inclinations has been made. The models were made of Parana Pine, Araucaria angustifolia. For the tests were performed three points bending. With the load values and the deflection at mid-span and by linear regression were determined the effective elastic modulus. The results indicate that the performance is reduced considerably in the presence of a scarf-joint in the external laminae and also the reduction is greater when the scarf angle increases.

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

2004 ◽  
Vol 38 (2) ◽  
pp. 119-126 ◽  
Author(s):  
Andrea Frangi ◽  
Mario Fontana ◽  
Adrian Mischler
Keyword(s):  
High Temperatures ◽  
Shear Behaviour ◽  
Glued Laminated Timber ◽  
Timber Beams

Non-Destructive Testing of Glued Laminated Timber Beams with Use of Pilodyn 6J – Method of Spike

2016 ◽  
Vol 825 ◽  
pp. 23-26
Author(s):  
Pavel Klapálek ◽  
Lenka Melzerová
Keyword(s):  
Modulus Of Elasticity ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Glued Laminated Timber ◽  
Measurement Results ◽  
Non Destructive ◽  
Timber Beams ◽  
The Way

This article is focused on GLULAM (glued laminated timber) beams and determination of their properties by using non-destructive method. This text is mainly focused just on part of more complex research of glued laminated timber beams. This text is focused on non-destructive method, which is the method of spike that uses device called Pilodyn 6J for measurement. Results of this method are in form of Young ́s modulus of elasticity. This article will describe how the method of spike works, with basic description, describes the tested material and compare the results of testing. In the conclusion we discuss the results, make conclusions and describe the way of our further research of glued laminated timber beams.

scholarly journals EVALUATION OF IMPACT OF ELEVATED TEMPERATURES ON YOUNG’S MODULUS OF GLT BEAMS

2021 ◽  
Vol 30 ◽  
pp. 41-47
Author(s):  
Lucie Kucíková ◽  
Michal Šejnoha ◽  
Tomáš Janda ◽  
Pavel Padevět ◽  
Guido Marseglia
Keyword(s):  
Mechanical Behavior ◽  
Elevated Temperatures ◽  
Tensile Tests ◽  
Experimental Results ◽  
Fire Tests ◽  
Dog Bone ◽  
Glued Laminated Timber ◽  
Crack Type ◽  
Variable Duration ◽  
Timber Beams

The influence of elevated temperatures on mechanical behavior of glued laminated timber beams is examined on the basis of tensile tests. Dog bone samples prepared from beams exposed to fire of variable duration were categorized with respect to the type and position of the failure crack, type and number of discontinuities such as knots, and the level of browning. The acquired experimental results suggest that the wood variability and the effect of growth discontinuities are probably more significant than the effect of elevated temperatures. To support this conclusion, further study is currently under way, exploring samples from the second series of the fire tests.

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