Experimental evaluation of the mechanical properties of Screw and Eucalyptus wood in different states – 2025

Abstract

Wood is one of the most accessible and widely used materials in the construction industry due to its versatility and availability. Tornillo and Eucalyptus wood exhibited similar dimensional contraction upon drying, with reductions of −2.835% and −2.85% per side, respectively. Tornillo showed a higher water absorption capacity (16.33%) compared to Eucalyptus (8.75%), despite having similar initial moisture contents (11.01% and 11.49%). In terms of basic density, Eucalyptus was denser (737.47 kg/m3) than Tornillo (493.34 kg/m3). In flexural tests, dry Eucalyptus demonstrated the best performance, with an average strength of 134.98 MPa and a modulus of elasticity of 12,745.35 MPa. Tornillo reached its highest strength in the natural state (77.41 MPa and 6,217.78 MPa), while its mechanical properties significantly decreased when wet. In axial compression, dry Eucalyptus also showed the highest resistance (948.12 kgf/cm2), representing a +72.37% increase compared to its natural state, while dry Tornillo reached 476.26 kgf/cm2 (+23.08%). Both materials showed notable decreases in strength when wet (−33.98% for Eucalyptus and −40.84% for Tornillo). Lastly, regarding Poisson’s ratio, Tornillo presented higher values in the wet (0.697) and natural (0.604) states, decreasing to 0.533 when dry. Eucalyptus, on the other hand, exhibited a slightly higher average in the wet state (0.650), followed by the natural (0.535) and dry (0.407) states. It was concluded that when wood is dried, its mechanical properties increase significantly; conversely, when it is subjected to a water absorption process, these properties decrease.