Numerical Simulation of LVL Elastic Modulus with Different Combinations of Mutually Perpendicular Veneer Layers

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UDС

691.116

DOI:

10.17238/issn0536-1036.2018.6.138

Abstract

Integrated composed supporting structures such as laminated plywood are the most sustainable in terms of material consumption in comparison with ordinary glulam structures of the same supporting capacity. However, design features and some manufacturing difficulties reduce the economic efficiency of laminated plywood structures. Appearance of Laminated Veneer Lumber (LVL) and possibility of using its various types instead of plywood walls and board belts can significantly increase the efficiency and expand the application area of composite structures of composed I-beam or box section. An important problem that limits development and common use of composed structures with LVL is the lack of information on value of the elastic modulus under different angles to wood fibers in LVL in current Russian design standards. This information is necessary for structure designing, for example, according to the method of transformed section. The article describes the creation of finite element models as well as the results of a finite element analysis of anisotropy of Ultralam LVL elastic modulus with different amount and combination of layers and mutually perpendicular and parallel arrangement of wood fibers. In the research, we have used numerical simulation of LVL bending tests using the FEM method according to GOST 33124–2014 in the SCAD program. The obtained data was processed in Mathcad and Excel software packages. Simple analytical dependences were obtained. They allow to calculate the elastic modulus of all types and thicknesses of Ultralam LVL at any given angle to wood fibers.

Authors

E.Yu. Tsiulin, Postgraduate Student
A.B. Shmidt, Candidate of Engineering Sciences, Associate Professor

Affiliation

Saint-Petersburg State University of Architecture and Civil Engineering, 2-ya Krasnoarmeyskaya ul., 4, Saint Petersburg, 190005, Russian Federation; е-mail: eciulin@edu.spbgasu.ru, shmidt.a.b@lan.spbgasu.ru

Keywords

Ultralam LVL, elastic modulus, finite element method, numerical experiment, wood structures, laminated veneer lumber, laminated wood structures

For citation

Tsiulin E.Yu., Shmidt A.B. Numerical Simulation of LVL Elastic Modulus with Different Combinations of Mutually Perpendicular Veneer Layers. Lesnoy Zhurnal [Forestry Journal], 2018, no. 6, pp. 138–148. DOI: 10.17238/issn0536-1036.2018.6.138

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Received on May 28, 2018