Determinações dos módulos de elasticidade e ruptura de madeiras por técnicas não destrutivas e destrutiva

Abstract

This work aimed to evaluate the use of non-destructive techniques (dynamic) by means of vibration frequencies (longitudinal and transversal) and stress wave and to relate the results with those obtained in destructive test (static) in determining the stiffness and strength of the four woody forest species. Planks with 200 × 40.0 × 5.0 cm (length × width × thickness) of Corymbia citriodora, Cordia alliodora, Manilkara sp. and Caesalpinia echinata were evaluated and the modulus of rupture (MOR) by destructive technique (static) and modulus of elasticity (MOE) by means of destructive and non-destructive techniques or dynamics (vibration transversal and longitudinal stress wave). For the analysis and evaluation of the results, a completely randomized design with four treatments (species) and 20 repetitions per treatment was used and the values, when significant F test (p ≥ 0.05), had their averages compared by Tukey's test (p ≥ 0.05). The evaluation of the relationship between static and dynamic techniques was through the Pearson's test. Eucalypts presented the highest values of elasticity and rupture modules. The transverse vibration technique provided the greatest correlation coefficients among the tested techniques. The best correlations among the MOEs were obtained by woods of lower specific gravities for the MOR was and no relationship among the specific gravities was observed.