A quantitative framework for multi-risk analysis of wind and rain on trees

Green spaces are among the most vulnerable areas in urban environments as they experience different levels of damage in extreme weather conditions. The stability of natural elements such as trees, which are valuable assets in urban areas, is threatened directly or indirectly by the occurrence of natural hazards such as wind, rainfall, and drought. This paper illustrates the conceptual foundations and the initial modeling steps of a novel approach for the conduction of multi-risk analysis for urban trees from the combined action of wind and rain. Operationally, the approach relies on the engineering modeling of the mechanical response of trees to the two risk agents and on the definition of vulnerability for relevant limit states.