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Woods
Published in M. Rashad Islam, Civil Engineering Materials, 2020
Common sawn timber products include solid timber beams and more rectangular timber sections. Glued laminated timber (glulam) is composed of several layers of dimensional timber, glued together with moisture-resistant adhesives. Round timbers and poles are very often used as columns, foundation piles, land and fresh water piles in ranch areas, or for decorative purposes. Prefabricated wood I-joists are very popular in floors, ceilings, and roofs nowadays. Laminated veneer lumber (LVL) refers to a composite of wood veneer sheet elements, with wood fiber primarily oriented along the length of the member. Parallel strand lumber (PSL) refers to a composite of wood strand elements with the wood fiber primarily oriented along the length of the member. Laminated strand lumber (LSL) is manufactured from flaked wood strands that have a high length-to-thickness ratio.
Falcataria-Rubber Wood LVL
Published in Peter J. Moss, Rajesh P. Dhakal, Progress in Mechanics of Structures and Materials, 2020
The old-growth trees and the average size of trees harvested to produce solid lumber continue to decline. The increase of the future demand of structural wood products and decline of the quality of wood resources will increase the development and the application of engineered wood products. LVL was developed in a response to a need for increased strength and stiffness, good dimensional stability, and low variability in engineered wood structural component. LVL products are used predominantly for residential and industrial structural building, such as roof truss, purlins, floor joists, etc.
Processing and recycling of timber
Published in Marios Soutsos, Peter Domone, Construction Materials, 2017
Laminated veneer lumber (LVL) is produced from softwood logs, which are rotary peeled to produce veneers 3 mm in thickness which, after kiln drying, are coated with a PF adhesive and bonded together under pressure to produce a large panel 24 m in length. This is then sawn into structural battens, and characteristic values for design uses, which are from 50% to 100% higher than corresponding structural softwood timber, are available from the two European and one Canadian manufacturer. The European specification for LVL is BS EN 14279.
Fatigue of glued-in rods in engineered hardwood products — part I: experimental results
Published in The Journal of Adhesion, 2019
S. Myslicki, O. Bletz-Mühldorfer, F. Diehl, C. Lavarec, T. Vallée, R. Scholz, F. Walther
Three types of rods were considered in this research: threated rods and different two types of rebars. The threated rods were M16–8.8 (abbrev. Thr. Rod), which a nominal diameter of ⌀ = 16 mm, and further specifications to be found in DIN 978; threaded rods consisted of stock material from the shop. The first rebar type was a standard B500B (Rebar, stock material) while the second type was an Inoxripp4486 (SST) composed of corrosion resistant steel grade 1.4482 (S32001, according to DIN 10088) delivered by Scheibinox/Germany; both rebars had a nominal diameter of ⌀ = 16 mm according to DIN 488. Three timber products, beech GLT, oak GLT and beech LVL, were used. All of them where mechanically characterised in a previous study,[1] as where the adhesives and the rods.
Experimental and numerical investigation of timber formwork beam under different loading type
Published in Mechanics Based Design of Structures and Machines, 2022
T. Ünal Dönmez, Abdullah Türer, Özgür Anil, R. Tuğrul Erdem
Such systems have been modularized into components to make the formwork systems easy to use in different structures. This modular approach enables the basic formwork system structure components to be installed effectively in a very short period. In the modular structure of formwork systems, it is one of the most important components formwork beam systems are becoming. Formwork beams are among the most important formwork system components that play an important role in forming formworks and carry their loads during the construction of the structural reinforced concrete system. Besides, the formwork beams are the most used and preferred components in a formwork system. Therefore, the formwork beams which are members intensely used in their lifetime. Within these periods of use, the beams may be under the influence of various types of loading, which create very different effects, such as static, fatigue, and impact loads. Formwork beams are produced by using timber or composite timber materials because they are economical, they are easy to carry because of their lightweight, and they have high resistance. Timber material is widely preferred in the production of such formwork systems since it is a type of material with high durability against environmental influences after being subjected to some processes. Today, instead of using wood material directly, the use of wood-based composite materials is preferred. Structural composite timber has been developed to reduce the consumption of forest resources and to meet the increasing demand for high-quality timber. Structural composite timber is being used as a replacement for raw timber in the manufacture of engineering wood products such as prefabricated wooden I-beams and in other various applications to benefit from higher engineering design values than those offered by the raw timber (Stark, Cai, and Carll 2010). Today, many other wood-based products such as Laminated Veneered Lumber (LVL) and Parallel Strip Lumber (PSL) are used for large-scale timber constructions. Similarly, these products are suitable for larger spans, such as flat glued laminate timber elements (Thelandersson 2003; (Stalnaker and Harris 1999).