Please cite this article in press as: D. Giaccone, et al., Inﬂuence of the geometric model on the structural analysis of architectural heritage, Journal of Cultural Heritage (2020), https://doi.org/10.1016/j.culher.2019.12.001 ARTICLE IN PRESS G Model CULHER-3696; No. of Pages 9 Journal of Cultural Heritage xxx (2020) xxx–xxx Available online at ScienceDirect www.sciencedirect.com Inﬂuence of the geometric model on the structural analysis of architectural heritage Domenico Giaccone ∗ , Pierluigi Fanelli , Ulderico Santamaria Dipartimento di Economia, Impresa e Società, Università degli Studi della Tuscia, via S. Camillo de Lellis, s.n., 01100 Viterbo, Italy a r t i c l e i n f o Article history: Received 25 June 2019 Accepted 5 December 2019 Available online xxx Keywords: Architectural heritage Stone column Finite element analysis Geometric model Viterbo a b s t r a c t Geometric models employed for structural analyses are usually strongly simpliﬁed, in order to make easier and faster the numerical solving. Sometimes this approach is valid and convenient as far as it does not inﬂuence the analysis results. However, depending on the circumstances and the objectives of the analysis, the model has to be accurately and precisely represented to capture the necessary outputs. This is the case with architectural heritage. In fact, in this ﬁeld, the surveyed objects are often characterised by complex forms and remarkable damages, which can affect the geometry signiﬁcantly. Nowadays, many techniques are available to obtain very detailed models of the surface of the object, but they do not allow to consider also interior damages or the constructive features. This information can be obtained through a careful knowledge and anamnesis of the object to study, based on visual inspection and instrumental measures. In this way, the creation of the model to undergoes to a structural analysis, consists in a synthetic operation conducted by the operator in a conscious way. This paper aims to prove that the results of a structural analyses can change signiﬁcantly, depending on the accuracy and the level of detail of the model. The study was conducted on a basic building element, that is a column, really existing and belonging to a monumental fountain. The column was modelled in ﬁve different ways which differ in the level of detail. An ultrasonic test was conducted on the real object to characterise cracks which were taken into account in the most accurate models. A comparison among the ﬁve models was done from a static and dynamic perspective, through the following analyses: static, buckling, modal and dynamic with response spectrum. © 2019 Elsevier Masson SAS. All rights reserved. 1. Introduction 1.1. Geometric models in structural analysis Structural assessment is based on the deﬁnition of an analytical model, that is a design scheme which takes into account geome- try, constrains and loads. According to the aim of the assessment itself, the analytical model can be more or less real. This means that the surveying object undergoes a simpliﬁcation process which is conducted by the operator and so, inﬂuenced by his skill and sensitivity. Simple models have been always preferred because they allow to make easier and faster the numerical solving of the structural problems. This approach is widely followed also in the ﬁeld of architectural heritage, despite complexities which characterise the Abbreviations: FEA, ﬁnite element analysis; US, ultrasonic. ∗ Corresponding author. E-mail addresses: d.giaccone@unitus.it (D. Giaccone), pierluigi.fanelli@unitus.it (P. Fanelli), santamaria@unitus.it (U. Santamaria). surveyed objects can reduce the reliability of the model and inval- idate the results. For instance, it has been recently used by Boscato et al., for the modelling of multi-leaf masonry walls damaged and consolidated [1]. Complexities which affect the architectural her- itage can be of different kind. They can be related to the geometry, the construction materials and techniques, and they can also derive from damages which modify the original shape of the building elements, such as static displacements, deformations, cracks, and loose of parts. Nowadays, a lot of computer programmes allow to make reli- able 3D models of the surveyed object to use in reverse engineering modelling applications. For instance, Lidar (Light Detection and Ranging or Laser Imaging Detection and Ranging) and photogram- metry are two of the most known and widespread techniques, used to do it. They allow to obtain very realistic models of the sur- veyed object with a great accuracy. Typical applications consist on the inventory of buildings which are in good conditions, and the assessment of the building deﬂections [2] or the out-of-plane of building elements (i.e. the fac ¸ ade) [3]. Moreover, they are espe- cially appreciated in organic un-rational contexts [4], that is when the investigated object cannot be described through the rules of the https://doi.org/10.1016/j.culher.2019.12.001 1296-2074/© 2019 Elsevier Masson SAS. All rights reserved.