Modulus of rigidityof commercially important wood species for Mexico: Pinus pseudostrobus, Tabebuia rosea and Quercus scytophylla

Abstract

Wood is a biological material with applications in engineering and architecture. Its modulus of rigidity is useful for the calculation of beams that work in bending and torsion. The objective of the research was to determine the rigidity moduli and material indices of Pinus pseudostrobus, Tabebuia rosea and Quercus scytophylla. Dynamic torsion tests were performed on 35 small specimens of each species. Linear correlations and their coefficients for determining the modulus of rigidityas a function of density and frequency were calculated. The main results are: The magnitudes of the wood densities of P. pseudostrobus, T. roseaand Q. scytophyllaare located within the interval:587 kg m-3, 735 kg m-3. The coefficient of variation of the frequencies for Q. scytophyllais 50% lower compared to the coefficients of P. pseudostrobusand T. rosea. The coefficient of variation for P. pseudostrobusis 23% greater than that of T. roseaand 146% greater than that of Q. scytophylla. It is concluded that the values reported in this research may be useful if these wood species are used for structural purposes.