Author: Branimir Šafran
- IMPACT OF THE LOAD RATE ON THE ELASTIC PROPERTIES OF BEECH WOOD SAMPLES AT COMPRESSION TEST IN THE LONGITUDINAL AND TANGENTIAL DIRECTION
Knowledge of dynamic elastic properties of wood is an important precondition for rational and effective exploitation of wood raw material. In this paper, the impact of the load rate on the elastic properties of wood at the compression test in the longitudinal and tangential directions is analyzed. Elastic properties which were determined in this research are the modulus of elasticity, stress and strain at the point of proportionality and specific energy and power of elastic deformation. The research was carried out on beech samples that were prepared with smaller dimensions than prescribed in the norm (DIN EN 408) in order to achieve a more accurate determination of the specific energy and power of elastic deformation. The load rate was varied from 2 to 50 mm/min.
Keywords: wood, Stress, strain, elastic area, load rate
- RESEARCH OF THE INFLUENCE OF ADDING ROTTEN WOOD ON THE MECHANICAL QUALITY OF PELLETS
This paper analyzes the effect of adding wood attacked by brown rot fungi to basic wood raw material with the aim of increasing the mechanical strength of wood pellets. Wood attacked by brown rot fungi has an increased share of lignin which is natural glue and can contribute to better mechanical properties of wood pellets. Wood pellets were produced on a single pellet press and pressed with adjusted production parameters at two different temperatures. Produced pellets were tested on some mechanical and physical properties. The analysis of experimental results has shown the statistical significant improvement of the mechanical properties of pellets by adding brown rot fungi wood.
Keywords: wood pellets, brown rot fungi wood, single pellet press, mechanical properties