Seismic Capacity Estimation of a Masonry Bell-Tower with Verticality Imperfection Detected by a Drone-Assisted Survey

Masonry towers are considered an important part of cultural heritage due to their architectural and historical value. From a structural perspective these kind of buildings are considered slender elements, the same as a cantilever beam. In real cases it is not easy to model with high accuracy these heritage constructions, since the geometry and mechanical properties of the constituent materials are not adequately known. On the other hand, a deep knowledge of the structural and seismic vulnerability of the masonry towers is needed in order to preserve and retrofit, when necessary, their architectural and cultural value. In the present research an exhaustive study is presented, as it regards the assessment of the seismic vulnerability of a heritage masonry bell-tower, built in the 14th century. An innovative protocol of structural survey followed, and it is proposed herein. The geometry of the tower was easily obtained by digital photogrammetry assisted by a drone. The geometrical model was easily converted into a digitalized input, that was introduced into a finite element method (FEM)-based code. The 3D model was used for linear static, linear dynamic and nonlinear static (pushover) structural analyses. The vulnerability of the masonry tower was assessed and at least one kinematic was found to be not verified.

Non-Destructive Tests on Carpentry Steels

Background: Industrial archaeology represents a modern branch of urbanism and architecture that studies, applying an interdisciplinary method, all the evidence inherent the process of industrialization from its origins to the actuality. Aim: Looking at the cities of our epoch, more and more are the testimonies of these historical artefacts, which in fact represent our cultural identity and are often intended to be recovered and converted into modern destinations of use. Methods: If the identification of constructive schemes is based on direct essays and surveys, the definition of material properties requires material testing and investigation. For metal structures, the standards involve destructive investigations only, with a sampling of specimens, which often conflict with the protection requirements of the artefact. This leads to the need to refine and make reliable non-destructive investigations using the Leeb method, by means of portable micro-durometers, for in-situ characterization of carpentry steels, so to suggest new regulatory guidelines for existing structures surveys. Results: In the paper, the classification of carpentry steels based on non-destructive hardness test was illustrated and discussed. Firstly, for the evaluation of the resistance class of a structural steel, it was recorded that the execution of tests required a careful cleaning of the surface of samples. Subsequently, analyzing the data obtained from the experimentation, it was clear that the best methodology of data conversion from micro-hardness (Leeb method) tests for the determination of the steel class was given by tables and formulations of the ASTM standard. In the case of a few values to be converted, the most effective method was the manual use of the tables, with an average error of 0.10%. Conclusion: In conclusion, it should be remarked that differently from the reinforced concrete structures, where the non-destructive tests are allowed by the current Italian technical code on, for metallic structures only, destructive tests are permitted, so that the use of non-destructive ones should be encouraged, especially when interventions on cultural heritage constructions are of concern.

Application of GUT Matrix in the assessment of pathological manifestations in heritage constructions

The present paper presents the application of GUT (Gravity, Urgency, Tendency) Matrix methodology as a tool in the assessment of pathological manifestations in buildings. Three heritage constructions of the historic center of Sobral, Ceará, Brazil were studied through in situ inspections, photographic records and elaboration of the damage map. The GUT Matrix was used as a tool to rank, in each building, priority levels for each damage in order to define their order of treatment. Thus, it was possible to conclude that the applied method can be used as a useful tool to manage the maintenance of buildings through prioritization of the most significant problems and, to contribute directly to the preservation and safety of the built historical heritage.

ANALYTICAL AND COMPARATIVE STUDY OF CHANGE IN FUNCTIONAL PURPOSE OF SOME ARCHAEOLOGICAL AND HISTORICAL ARCHITECTURES IN CAIRO DURING THE 19TH AND 20TH CENTURIES

This research paper aims to discuss the nature of change in the functional purpose of some archaeological and historical buildings in Cairo during the 19th and 20th centuries along with a comparative study of some of the most important heritage constructions and evidences in the world, such as the British Museum in London, as well as the Historical Railway Station of Orsay in Paris. There are some practical attempts and technical procedures that have been carried out to achieve some functional purposes, differ from the original purposes of the archaeological and historical buildings in Cairo in particular. In a similar way, this has been applied to historical and heritage buildings around the world in general. The methodology of this study will be addressed through analytical and comparative study of the original idea or the original functional purpose of these archaeological and historical buildings.The outlines and features of change in the functional purpose of these archaeological and historical buildings are represented in some technical procedures like the technique of adaptive rehabilitation or rehabilitation in terms of adaptation, so there is a necessity for conformity and harmony between heritage buildings and modern functional purpose, and this should be done without any disagreement and repulsion with the original functional purpose. There is also a necessity to protect the original functional purpose, which should be adapted to the modern functional purpose in order to achieve compatibility between old and new integration processes.

Structural Health Monitoring for cultural heritage constructions: a resilience perspective

<p>Disturbances or disruptive events may induce reductions of functionality of the built environment. For Cultural Heritage (CH) structures, functionalities may range from technical, to economic ones linked to touristic activities, up to intangible functionalities related to the cultural and social value of these constructions. Resilience can be defined as the capability of a system overcome a disturbance with the minimum total loss of functionality over time. Structural Health Monitoring (SHM) may enhance resilience by providing information that can support decision making, aiming to reduce the impact of the disturbances. In this paper, the benefits of SHM systems as means for improving resilience of CH structures are addressed and discussed with specific reference to the three different decision situations; before, during and after events of disturbances. Examples of real applications of SHM for CH structures and its effect on the resilience of the system conclude the paper.</p>

Dynamic characterization of a heritage construction from 19th century

Heritage constructions presents high significance and importance for society. As way of contribution for the preservation of the heritage constructions, this paper presents a study on the dynamic behavior of a heritage construction, part of the historic center of Sobral city, located at the north region of Ceará State, namely the Nossa Senhora das Dores Church, a church from the beginning of the 19th century, built in clay brick walls. In this study, ambient vibration tests were performed aiming to obtainment of the natural frequencies of the building focusing the calibration of the numerical model and, from it, proceeding with modal analysis by Finite Element Method (FEM) with recurrence to software Ansys®. The results allowed the analysis of the structural dynamic behavior taking into account natural frequencies, modal shapes and directional displacements.

AMBIENT VIBRATIONAL CHARACTERIZATION OF THE NOSSA SENHORA DAS DORES CHURCH

The present paper shows the vibrational characterization tests of a clay brick heritage construction from XIX century, the Nossa Senhora das Dores Church, placed in Sobral, Brazil. In this study the calibration of the 3D finite element numerical model of the church was performed through ambient vibrational testing using the first three natural frequencies identified. The obtained results, namely the natural frequencies identified, and the calibrated model intends to give a contribute for understanding of the structural behavior of the Brazilian heritage constructions, and introduces relevant information for be used for safety assessment of the church along the time.