Mechanische Eigenschaften der Fichte: Experimente zur Analyse von Naturgefahren | Mechanical properties of Norway spruce: Experiments for the analysis of natural hazards Open Access

Among others, the protective effect of the forest against natural hazards is mostly co-determined through the mechanical stability of the trees. Despite this, there is a lack of quantifiable knowledge regarding the mechanical interaction between the trees, the forest and natural hazards. With experiments conducted on spruce trees,and mechanical modelling of trees and tree trunks, the mechanical properties and the energy absorption capacity for a single tree during a rock impact were determined. It was shown that the anchorage properties correlated well with the volume of the tree stem. The four-point bending tests and the dynamic impact tests enabled us to determine the strength of the tree stems. Furthermore, the obtained values for the strength of the tree stems were strongly affected by the wood quality and sometimes deviated substantially from the established material properties of dried wood used for buildings. The behavior of trees when impacted by rocks could be simulated with full-scale impact tests and the energy absorption capacity quantified. These experiments gave important knowledge of how to analyze the interaction between natural hazards, trees and forests,with the focus on Norway spruce. However, to quantify the protection effect of the forest against natural hazards,more experiments on different tree species are required.