Vibrational problems of timber beams with knots considering uncertainties

A stochastic model of the dynamic behavior of sawn timber beams of Argentinean Eucalyptus grandis is herein presented. The aim of this work is to study the influence of the timber knots in the dynamical response of timber beams. The presence of knots is known to be the main source of the lengthwise...

Descripción completa

Detalles Bibliográficos
Autores: Garcia, Diego Alberto, Sampaio, Rubens, Rosales, Marta Beatriz
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/47335
Acceso en línea:http://hdl.handle.net/11336/47335
Access Level:acceso abierto
Palabra clave:Timber Beams
Knots
Uncertainties
Natural Vibration Frequencies
Natural Vibration Modes
Composite Materials
https://purl.org/becyt/ford/2.1
https://purl.org/becyt/ford/2
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:A stochastic model of the dynamic behavior of sawn timber beams of Argentinean Eucalyptus grandis is herein presented. The aim of this work is to study the influence of the timber knots in the dynamical response of timber beams. The presence of knots is known to be the main source of the lengthwise variability and reduction of bending strength and stiffness in timber beams. The following parameters of the timber knots are considered stochastic: position along the beam span and within the beam cross section, shape and dimensions. Experimental data, obtained from bending and density tests, are employed to find the timber modulus of elasticity (MOE) and density. On the other hand, the characteristic of the timber knots used in the stochastic model was obtained from a visual survey performed with 25 beams of the same species. The problem of the natural vibration frequencies of the timber beam is approximated with the finite element method. Numerical results are obtained using Monte Carlo Simulations (MCS). The uncertainties of the timber knots parameters and their influence are quantified with the probability density function (PDF) of the frequencies. Statistical results obtained by means of MCS are compared with experimental measurements in order to assess the accuracy of the stochastic model. The present approach that gives a more realistic description of timber structures, correlatesbetter with experiments.