TY - JOUR AU - Rebko, Дмитрий AU - Kamlyuk, Андрей AU - Borisevich, Сергей PY - 2017/08/14 Y2 - 2024/03/29 TI - Models of behavior of forests under influence of wind loads JF - Journal of Civil Protection JA - JCP VL - 1 IS - 3 SE - Safety in emergencies (technical sciences) DO - 10.33408/2519-237X.2017.1-3.323 UR - https://journals.ucp.by/index.php/jcp/article/view/84 SP - 323-331 AB - <p><em>Purpose.</em> To analyse two independently mathematical models (GALES and HWIND) for predicting the critical wind speed and turning moment needed to uproot and break the tree stems.</p><p><em>Methods.</em> The GALES model calculates the aerodynamic roughness and zero-plane displacement of a forest stand. The aerodynamic roughness provides a measure of the stress (force: unit area) imposed on the canopy as a function of wind speed and the zero-plane displacement provides a measure of the average height on the tree at which the wind acts. This allows calculation of the bending moment imposed on the tree for any wind speed, as a result is the model to make predictions of the wind speed at which the tree will be overturned and broken. In the HWIND model the turning moment arising from the wind drag on the crown is calculated assuming a logarithmic upwind profile. Based on the sum of wind load and the contribution from the overhanging weight of the stem and branches the total bending moment is calculated. The breaking strength of the stem and the support given by the root-soil plate are calculated from previous experiments.</p><p><em>Findings.</em> This allows calculating the wind speed required to break and overturn the tree.</p><p><em>Application field of research.</em> Forecasting the consequences of emergency situations connected with strong winds. Conclusion. Models comparisons showed that it is necessary to improve existing models and to develop new ones which will be more accurate.</p> ER -