Valerio Sabbatini

1. As a result of the exponential development of information technologies, the existing architectural, engineering, and construction sector has also undergone a decisive change. The disciplines of ...

A comprehensive study was carried out to integrate information from different sources and evaluate the effects of induced vibrations on a temple. Historical analysis was fundamental to interpreting the evolution of the construction and defining the HBIM. Experimental data were implemented in the FEM of the site, including the temple, its foundations, and the soil stratifications. Sensitivity analysis was carried out to identify the most influential parameters, which were calibrated to reduce error with the experimental frequencies. The FEM was further optimized with the Douglas–Reid method, considering, simultaneously, modal frequencies and deformations. Two different nonlinear dynamic analyses were performed; one analysis studied the effect on the temple of the dynamically moving load of the tram, and the other analysis studied the response of the temple to three-dimensional accelerations applied at the base. The drawbacks of each simulation were identified by comparing the numerical and experimental results.

Nowadays, the research in the fields of conservation and restoration is focusing on recording large amounts of data and information in order to obtain highly accurate surveys that include most details of constructions. Documenting and surveying are fundamental activities in achieving the successful preservation of cultural heritage, but also in implementing efficient strengthening interventions of structures. The applications of methods and techniques that link the disciplines of geometrical surveys and structural analyses are still fragmented, and further research is necessary to fully transfer site information into structural models. In this article, the authors propose a methodology with which to link different restoration fields, with the aim of highlighting the strengths and weaknesses of the interoperability between surveys (carried out through detailed restitution from point clouds), heritage building information modeling (HBIM), and structural analyses to connect three different disciplines. The goal is to find a synthesis model that brings together historical and geometric characteristics, but also physical–mechanical properties, for a structural evaluation through a finite element model (FEM). The case study of the Escuela José Mariano Méndez is analyzed, an extremely damaged historical adobe building in Santa Ana, the second largest city of El Salvador; it is considered fundamental to the national economy, particularly after the “coffee boom” in the late 1800s. The site, located near the historic center, is also known as “Antigua Escuela de Artes y Oficios” and embodies the architectural traditions of the region, being built in adobe and stone. Roma Tre University and the Secretaría de Cultura de la Presidencia (SECULTURA) are partners in this research project to document and restore the historical and cultural value of this site.

In Roman Baths, the Romans employed barrel and groin vaults of great dimensions, with maximum span more than 20 m; simple tools of structural analysis of ancient wide span vaulted halls are still lacking, due to geometrical and material complexity. In this paper, we study the collapse behavior, under horizontal static action, of a corner cross vault of the Baths of Diocletian in Rome (Hall I). Two methods of analysis are here used: non-linear incremental finite element and limit analysis. In both cases, 3D models have been developed by means of UAV inspection, NDT measures, and AVT monitoring. The construction of the overall 3D geometry has been here afforded with a specific pre-processing approach. Midas commercial software has been employed for FEM analysis, assuming a constitutive law specifically developed for Roman concrete. In limit analysis, masonry is discretized as a system of interacting rigid bodies in no-tension and frictional contact. The computational code consists in a linear approach, which makes use of a series of optimization packages via lower and upper bound techniques. Finally, a strategy based on FEM analysis including discontinuities was implemented, and the results were compared with the two previous approaches.

Analysis and diagnosis of historical masonry buildings are frequently affected by uncertainties due to unexpected behaviors caused by cumulative damage, material decay or transformations. This research work follows a methodology in the structural analysis of the historical masonry church of San Filippo Neri in Macerata, severely damaged after the Central Italy Earthquake occurred in October 2016. The PRiSMa laboratory (Proof testing and Research in Structures and Materials) of Roma Tre University carried out an extensive onsite testing campaign, including NDT tests as sonic tomography and endoscopy, and minor destructive technique as double flat jack test, together with dynamic monitoring under ambient vibrations, to investigate the state of conservation of the building. The onsite testing results were then implemented in an accurate finite element model, which was tuned up by means of global dynamic response provided by OMA (operational modal analysis) and updated, after the sensitivity analysis, through the Douglas-Reid method. Finally, nonlinear static and dynamic analyses were performed to investigate the state of damage of the church and reduce its uncertainties. This methodology will support the design of strengthening measures to achieve a higher level of safety concerning both needs of protection and conservation, thereby avoiding ineffectual or amiss interventions.

The growing use of highly specialized tools has led to a better knowledge of the mechanical properties of the structures, reducing the destructive tests. The paper is aimed to identify an investigation method capable of directing staff in the planning of non-destructive test. The experimental campaigns must be planned in order to optimize the number and the type of tests to limit invasiveness and impact. The proposed method has been organized in a logical scheme that permits, in five steps, to predict with a good approximation the critical sections for an optimal setup of testing instruments. This method has been applied to the Octagonal Hall in Diocletian’s Bath, to establish a better location for the dynamic endoscopy and tomographic tests. A geometrical model was built using the plans, elevations, sections provided by the National Roman Museum and the point cloud made through a drone. With HBIM (Heritage Building Information Modeling) it was possible to synthesize the information obtained from the geometric and material survey and then to convey it to a finite element model built on Midas Fea NX. Then, structural analyses, both linear and nonlinear, have been carried out for the optimal test setup.

Understanding the behavior of historic structures that have undergone structural changes, restorations, and damage over time is still a significant challenge for structural engineers, particularly in those countries subject to high seismic risk, such as Italy. The study of built heritage for its prevention and conservation is an active research topic, due to the numerous uncertainties present in historic structures. Finite element modelling has become the most common and accessible method to study the behavior of complex masonry structures, however, the gap between numerical and experimental analysis may lead to erroneous results. Model updating techniques can reduce the discrepancy between the behavior of the numerical models and the testing results. The goal of this work is to illustrate a methodology to integrate the information derived from local, global, and geotechnical investigations into the finite element model of the masonry historical church of San Giovanni in Macerata, considering the Douglas–Reid model updating method. The PRiSMa laboratory of Roma Tre University carried out local investigations such as sonic tomography, video endoscopy and double flat jack tests, along with five ambient vibration tests that were processed through the operational modal analysis to extrapolate the dynamic properties of the building (modal frequency, modal shape vector and modal damping). The combined use of global, local and geotechnical information implemented in the methodology effectively reduced the uncertainties of the model and led the refinement and validation of the most relevant structural parameters.