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The application of non-destructive technologies for the assessment of mechanical properties has been increasingly used due to its reliable assessment of the condition of timber elements. The application of such methods is well established for sawn timber and small-diameter roundwood. However, regarding the assessment of the mechanical properties for roundwood with larger diameters, which are usually used for new utility poles, a fewer number of studies are available. This research considered three different methodologies for application in Maritime Pine utility poles: i) longitudinal vibration, ii) transverse vibration, and iii) ultrasound. The methodology with better results was chosen for use in the second stage of testing. Furthermore, mechanical tests were performed to compare and validate the results from the non-destructive tests. The moisture contents and densities were also determined. Simple and multiple linear regression analyses were performed between the visual, dynamic, and mechanical properties. The longitudinal vibration method achieved the best correlation within the non-destructive methods, while the ultrasound method had no noticeable correlation. The vibration frequency (f) (r = 0.51) showed a better correlation with the bending strength (MOR) than the dynamic modulus of elasticity (MOEdyn) (r = 0.45). The static modulus of elasticity (MOE) was the best property used to predict MOR because it presented the highest correlation (r = 0.79).

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This study quantifies and compares the environmental impacts of production systems of biomass and roundwood from different wood species—maritime pine, eucalyptus, and cryptomeria. The results showed that roundwood and biomass from eucalyptus had the highest environmental impacts in most of the environmental categories. In contrast, cryptomeria products had the lowest impacts. For biomass, the impacts were higher for the forest production scenario when less biomass was produced (eucalyptus). The literature review showed that one of the main topics under study in the quantification of the environmental impacts of biomass is the allocation methodology. Thus, this study compared the environmental impacts of the various scenarios considering different methods of allocation: sub-division of processes, volume, mass, economy, and energy. The results showed that, for most scenarios, the biomass environmental impacts calculated by subdivision of processes had the highest values. In contrast, the environmental impacts of biomass calculated by economic allocation had the lowest environmental impact in most scenarios. The impacts of mass and energy allocation were similar for both products in all scenarios. Furthermore, this study showed that the system boundaries in biomass production have a strong influence on the environmental impacts and require further research.