Windloads
Models from Eurocode 1 and DIN 1055-4
Vibration dynamics of trees in the wind
The effects of wind on trees are determined by numerous influencing factors. Although they cannot be predicted exactly, load assumptions are indispensable for safety considerations. Arbostat offers a comprehensible way of estimating expected wind loads that can occur in trees.
Wind parameters based on standards
Arbostat follows the mathematical approaches of Eurocode 1 and uses terrain categories, which are included in national standards for building aerodynamics, to estimate how the buildings and topography in the vicinity of a tree affect the structure of the wind. In addition, adjustments can be made to small-scale flow influences, e.g. from neighboring buildings or trees.
Evaluation of the dynamic behavior
Vibrating structures react dynamically in a turbulent wind flow. While resonance can lead to an upswing resulting in an increased risk of failure, force peaks can be cushioned or reduced by damping, triggered by movements of the branch structure of a tree. These phenomena have been scientifically investigated on trees in recent years. The dynamic behavior of trees is integrated into the calculations in the ArboStat and TreeCalc software.
Equivalent static wind load
ArboStat provides the latest research results for estimating the vibration properties of trees. In accordance with DIN 1055-4, an equivalent static load is calculated that causes the same deflection as a gusty storm. This allows the results of tree static measurement methods (e.g. tensile tests) to be compared with dynamic wind effects.
