Correlation of Bending Test Varying the Length Between Supports to Determine Longitudinal Modulus of Elasticity

摘要

The large amount of wood in Brazil related to the numerous uses of this material stimulates many studies to be carried out in order to use this raw material increasingly in a rational and adequate way. Compared with concrete and steel, wood presents an excellent relation between mechanical strength and its mass, beauty, low energy consumption for its processing, good thermal insulation and easy workability. In order to make the best use of wood, this work proposes to study the correlation between the values of the longitudinal modulus of elasticity (E) obtained in the 3-point bending test with a 14H and 21H (H = height of cross-sectional area) of specimen measurement between the supports. The data were analyzed through linear regression analysis, thus, three correlations were calculated between values from 14H of span length to the other 21H of span length in the test for a particular correlation of each hardwood species (Peroba Rosa and Eucalyptus Tereticornis ) and the third one was generalized for the use in more hardwood species. Thus, the correlation of the longitudinal modulus of elasticity for the species of the hardwood group was possible for: Peroba Rosa (Aspidosperma polyneuron ) with 35 specimens and Eucalyptus Tereticornis (Eucalyptus tereticornis ) with 33 specimens.