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The preservation of trees in urban and archeological areas is a theme of particular relevance. Modern systems of monitoring, together with approaches for deriving the main characteristics of trees influencing their response toward extreme events, are nowadays at the basis of a growing number of studies. The aim of the present paper is the dynamic identification of trees carried out by employing an approach which combines a simple data-acquisition system, direct and ambient sources of excitation, and different data-processing methods. In particular, using a single accelerometer placed at different sections of the trunk and considering excitations induced by either pulling tests or ambient vibrations, the derivation of the main frequencies and levels of modal damping characterizing the dynamic response of a sour cherry tree (Prunus cerasus) is carried out. A finite element model of the tree is also carried out to support the validation of the proposed approach and further analyze the derived outcomes. The obtained results underline the feasibility of the proposed approach in deriving information useful for assessing the behavior of trees toward dynamic actions and, consequently, of particular relevance for the identification of possible damages induced by variations in terms of dynamic characteristics (frequencies) and damping.

The conservation of the historical and artistic heritage is one of the main priorities of Italian and international policy. The great variety of masonry buildings that make up this heritage is characterized by different combinations of materials and construction techniques. Then, several damage scenarios could be observed as a result, requiring appropriate retrofitting interventions. A rather accurate structural behavior analysis, especially for horizontal load conditions, allows for elaborating a correct seismic assessment. Albeit there are various numerical tools available to examine them, each one’s process starts by means of certain assumptions that could not be applied indiscriminately. This paper aims to compare two different types of modeling techniques to evaluate their strengths and weaknesses. To achieve this goal, an earthquake-damaged complex in Central Italy was chosen as a case study. The structure was modeled using a finite element (continuous) and a distinct element (discontinuous) method. Both approaches underwent a nonlinear dynamic analysis using the strong motions recorded during the 2016 seismic sequence. The results show that both approaches can evaluate the weak structural points. However, in some cases, the distinct element method appeared more accurate in reproducing the cracks.