Search

Finite-element-models are usually employed to simulate the behaviour of historical constructions. However, despite the high complexity of these numerical models, there are always discrepancies between the actual behaviour of the structure and the numerical predictions obtained. In order to improve their performance, an updating process can be implemented. According to this process, the value of the most relevant physical parameters of the model is adjusted to better mimic the actual behaviour of the structure. For this purpose, the actual structural behaviour is usually characterized via its experimental modal properties (natural frequencies and associated vibration modes). For practical engineering applications, the maximum likelihood method is normally considered to cope with this problem, due to its easy implementation together with an understandable interpretation of the updating results. However, the complexity of these numerical models makes unfeasible the practical implementation of the process due to the simulation time required for its computation. In order to shed some light to this problem, a new combinative computational algorithm is proposed herein. Additionally, the performance of the proposal has been assessed successfully via two applications: (i) a validation example, the model updating of a laboratory footbridge, in which the practical implementation of the algorithm has been described in detail; and (ii) a case-study, the model updating of a complex historical construction, in which the main advantage of the proposal has been highlighted, a clear reduction of the simulation time required to solve the updating problem without compromising the accuracy of the solution obtained.

San Cristóbal’s is a porous sandstone that is present in masonry structures of numerous historical buildings located in the southwest of Spain (15th–18th centuries). In order to guarantee conservation and structural integrity, most of these structures have been assessed during the last two decades after they presented severe damages in locations affected by moisture. In this study, static and dynamic elastic modulus and uniaxial compressive strength of San Cristóbal’s stone are determined in the laboratory under dry and saturated states, as well as with a moisture content of 40%, to establish the influence of moisture on them. An experimental campaign was conducted on 16 samples of ancient stone, extracted from the core of structural walls and columns during a structural intervention. The results show how the moisture content directly affects the deformability of the stone, especially between dry and 40% moisture content states. The values of the elastic modulus, both static and dynamic, are reduced with average values of 16.98% and 22.85% respectively. The loss of uniaxial compressive strength between the dry and saturated states is established with a mean value of 29.82%. Additionally, empirical relationships between the studied mechanical properties have been developed, reaching coefficients of determination over 0.90 in most cases.

The purpose of this paper is to bring the numerical models' structural behavior closer to the real behavior of the Church of Santa Ana in Seville, in Triana, through the development of high-definition geometric models that incorporate the non-linear materials' behavior. This church is presented as a unique case study due to the geometric complexity of its vaults and the influence on the structural behavior of the constructive solution of its passable roof. A geometrical model has been developed “as i”t, adapting the various constructive solutions to the real building. The result is a ”high definition geometrical model”. To define the materials a dynamic identification campaign has been carried out using OMA (Operational Modal Analysis) that has allowed us to adjust the mechanical properties of these materials in the numerical models. Modal shapes and frequencies of vibration similar to those obtained in the environmental vibration campaign has been obtained. A first linear analysis give us an approximation and a magnitude order of the displacement levels and the stress state, and let us to locate areas that exceed the admissible level stresses of the defined materials. With these results and analyzing in situ the displacement levels using photogrammetry, we decide to implement in the numerical analysis a constitutive model that contemplates the nonlinear behavior of these materials with Concrete Damage Plasticity model in Abaqus Cae. A non-linear analysis has been performed increasin the gravity factor until the structural collapse to determinate the structural safety factor.

This article presents an innovative metamodeling approach for predicting the effective elastic properties of cement grouts containing carbon nanotubes (CNTs), for the purpose of structural rehabilitation. The study addresses the homogenization of nano- and micro- scales through a Representative Volume Element (RVE). The numerical model consists of a cement matrix doped with randomly oriented CNTs, yet the computational load associated with this model poses a significant processing limitation. To overcome this challenge, a metamodeling approach based on a Kriging surrogate model is proposed. This approach provides a fast and accurate alternative to bypass the timeconsuming numerical homogenization process. The surrogate model establishes a connection between the microstructural characteristics of CNTs, cement, and the effective elastic properties of the composite grouts. The accuracy and efficiency of the proposed metamodel are demonstrated through detailed analyses.

El análisis y la evaluación de la integridad estructural del patrimonio arquitectónico de las ciudades modernas es actualmente un elemento clave para su correcta conservación. Es bien sabido que una de las principales dificultades que se pueden detectar en un análisis estructural numérico basado en modelos de elementos finitos de este tipo de edificaciones es el alto nivel de incertidumbre asociado a numerosos factores que inciden en el comportamiento de la estructura. Los cambios en las propiedades mecánicas de los materiales estructurales, la interacción suelo-estructura o incluso el proceso de construcción del edificio pueden ser la causa de grandes diferencias entre los resultados obtenidos de un análisis numérico y otros estimados experimentalmente. En este sentido, el uso de técnicas no destructivas como las pruebas de vibración ambiental y el método de análisis modal operacional están muy extendidos como proceso para identificar propiedades dinámicas de estas construcciones históricas. La actualización del modelo de elementos finitos, a partir de los parámetros dinámicos identificados experimentalmente, permite ajustar estos modelos para obtener una estimación más precisa del comportamiento de la estructura. En el presente trabajo, se describe la implementación de todas estas técnicas en la iglesia del Real Monasterio de San Jerónimo (Granada, España), una iglesia de estilo renacentista (1504) declarada Monumento Histórico Artístico en el Catálogo General del Patrimonio Histórico Andaluz por lo que tiene grado de protección como Bien de Interés Cultural. Se utilizan pruebas de vibración ambiental y el método modal operacional para obtener las frecuencias y formas modales del edificio. El proceso de actualización implica la comparación de parámetros experimentales (frecuencias naturales y formas modales) con los valores equivalentes de un modelo numérico. Una vez finalizado este proceso, se obtiene un modelo de elementos finitos con un comportamiento dinámico

This work presents a relationship between static and dynamic elastic moduli for San Cristóbal’s stone, which was used to build some of the most representative historical constructions in Andalusia (Spain) during 15th-18th centuries, including religious, military and civil buildings. Numerical models are able to provide useful information in structural health assessment of historical constructions, but static elastic modulus is necessary to perform them. This is why it is particularly interesting to count on an equation to predict this parameter from others, such as dynamic elastic modulus, which can be obtained in situ and through tests based on wave propagation. A new relationship is proposed after having shown that equations previously defined by other authors are not valid for San Crist´obal’s stone. The prposed relationship in this work is based on a set of physical and mechanical experimental tests carried out in lab on 17 specimens directly extracted from support elements of Santiago’s (Jerez de la Frontera, Cádiz-Spain). Linear, polynomial and nonlinear multiple regressions were considered, as well as the inclusion of other parameters, such as bulk density and porosity. However, an equation with a coefficient of determination of 0.95 was achieved with a simple regression where only dynamic elastic modulus was involved. This simple equation allows to predict static modulus of San Cristóbal’s Stone with a high level of confidence and only from one parameter, that can be obtained in situ through non-destructive techniques and respectfully to built heritage. Finally, a first approximation to the application on an ancient construction is provided. Six columns of the Monastery of San Jerónimo de Buenavista, in Seville (Spain) underwent tests based on the propagation of wave to determine in situ their dynamic elastic modulus. The In situ results for the dynamic elastic modulus are consistent with those obtained in lab.

The assessment of the structural health of historical constructions is needed to carry out correct diagnoses and implement proper decision making strategies in the preservation built cultural heritage. In order to provide information about the state of different structural elements of the Monastery of San Jer´onimo de Buenavista, in Seville (Spain), an extensive experimental campaign, mainly comprising non-destructive and in situ tests, was carried out. The present paper describes a structural analysis based on numerical models. The main goal of this research is to assess the improvement in the results of numerical model by integrating information from techniques which come from fields of knowledge that complement architecture and engineering, such as geophysics, archaeology or topography. A non-linear analysis under gravitational loads until reaching the ultimate load of the structure is developed. A model that is truer to the reality at a global level is obtained, highlighting significant improvements in the results at a local level.

In recent years, Structural Health Monitoring (SHM) based on Operational Modal Analysis (OMA) and damage detection tools has become a popular non-destructive solution to assess the real-time integrity of any kind of structure. This technique is especially well-suited for the condition-based conservation of historical structures, where minimal invasiveness must be ensured owing to their high cultural and architectural value. Optimal Sensor Placement (OSP) techniques represent a valuable tool for efficiently designing the sensor layout in a SHM system in order to achieve an effective modal identification with a reduced number of sensors and, consequently, an improved cost efficiency. In this light, this paper proposes a design methodology of sensor networks based on OSP techniques suitable for historical structures. To do so, a preliminary extensive OMA campaign is conducted in order to construct a reliable finite element (FE) model by fitting the identified modal properties. Afterwards, an optimal sensor arrangement with a limited number of sensors is obtained by applying different model-based OSP techniques. In order to improve the robustness of the solution, material uncertainties are included in the model and the optimal sensor placement is conducted within a statistical framework. This methodology is presented and evaluated with a case study of a Spanish secular building: the Monastery of San Jerónimo de Buenavista in Seville (Spain). In particular, this paper presents the results of the preliminary ambient vibration test and the modal identification of the monastery, the updating process of the FE model, as well as a critical review of the different OSP techniques within a framework of material parameter uncertainty. The presented analysis demonstrate that OSP techniques based on the rank optimization of the kinetic energy matrix of the structure yield robust sensor layout.

The finite element model (FE) updating is a calibration method that allows minimizing the discrepancies between the numerical and experimental modal parameters. As result, a more accurate FE model is obtained and the structural analysis can represent the real behaviour of the structure. However, it is a high computational cost process. To overcome this issue, alternative techniques have been developed. This study focuses on the use of the unscented Kalman filter (UKF), which is a local optimization algorithm based on statistical estimation of parameters taken into account the measurements. The dome of a real chapel is considered as benchmark structure. A FE model is updated applying two different algorithms: (i) the multi-objective genetic algorithm and (ii) a hybrid unscented Kalman filter-multi-objective genetic algorithm (UKF-MGA). Finally, a discussion of the results will be presented to compare the performance of both algorithms.

Santa Ana Church (1.266) is one of the main milestones in the heritage of Seville for being the first Christian church built outside the city walls and on the other side of the river, after the Reconquest of the city. The singularity of the geometry of its vaults together with its execution in brick and stone masonry make complex to determine the properties of materials. The impossibility of characterizing these materials by means of destructive tests leads to the application of other non-destructive technologies that allow us to approach the behavior of the numerical models to the reality performed. This paper tries to determine the mechanical properties of the materials that constitute the structure of the church of Santa Ana, which are brick and stone masonry, through analyzing its dynamic behavior with environmental vibration techniques and modal operations analysis (OMA). After having carried the campaign out using the methods of modal identification in the stochastic subspace and in the frequency domain, four vibration modes are obtained that adjust to the modal behavior of the current building, within a frequency range between 2 and 4 Hz. Initially, and thanks to new techniques such as photogrammetry, it has been possible to develop a finite element model (FEM) to analyze the structure with theoretical parameters of its materials. With this model and through the environmental vibration technical it is possible to conclude with the suitability of the application of a non-destructive method in heritage buildings to extract the mechanical properties of the materials that constitute its structure through its dynamic behavior.

Today’s society is sensitive to the architectural heritage conservation. This implies to perform works to maintain these buildings and to assure their structural security. In the last years, the structural analysis of historical masonry constructions has experienced a great progress, thanks to the use of techniques based on the study of the dynamic properties of building structures. In this context, changes on the structural health state of a building are one of the elements that can be assessed considering changes on their dynamic properties. This is useful to evaluate the effectiveness of structural interventions on this kind of buildings by analysing these properties before and after it. This paper focuses on the Jura Chapel, in Jerez de la Frontera (Spain). This chapel is part of San Juan de los Caballeros Church and is dated from the 15th century. In 2015 and after the identification of some structural damages in the chapel vault, an intervention was initiated to improve its structural behaviour and to recover its original appearance. The present work reports the evaluation of the effects that this intervention has on the structural health state of the building, using nondestructive techniques based on ambient vibration tests (AVT) and Operational Modal Analysis (OMA). The AVT were performed for both prerestored and restored states and under environmental loads. A discussion about the validity of doing AVT from extrados when a vault presents disconnection between ribs and web is included in the paper. As a result, the first five natural frequency values have increased while the corresponding mode shapes have not changed significantly. This proves a structural health improvement caused by the repairing process without changing the original behaviour of the structure. This work shows OMA capabilities for evaluating the effectiveness of intervention works on the health state of a historical masonry structure.

La alteración de la Piedra arenisca es una inquietud para los técnicos y restauradores del patrimonio histórico, ya que es la piedra base de muchos edificios de nuestro patrimonio histórico. En este trabajo nos vamos a centrar en la piedra extraída en el Cerro de San Cristóbal, situada en el Puerto de Santa María (Cádiz). Una de las características de esta piedra es un material muy degradable, que unido a las alteraciones provocadas por el paso del tiempo y por los agentes atmosféricos están poniendo en peligro parcial o totalmente algunos de los edificios históricos más importantes de nuestra región. El objetivo de este trabajo consiste en contribuir a la caracterización mecánica de la piedra del Cerro de San Cristóbal, utilizando métodos físicos y geofísicos. Para desarrollar este trabajo contamos con una serie de probetas pertenecientes a la Iglesia de Santiago de Jerez de la Frontera, las cuales se han obtenido extrayendo varios testigos en el sentido paralelo al eje de las columnas. La caracterización de sus propiedades físicas se ha centrado en la determinación de su densidad, (seca, sumergida y saturada), porosidad abierta, absorción, volumen de poros, volumen aparente, mientras que sus propiedades mecánicas se ha determinado mediante ensayos dinámicos, determinando su módulo de deformación identificando sus frecuencias naturales de vibración. Dicha campaña dinámica se ha realizado a diferentes niveles de humedad seca 0%, y saturadas al 40%, 80% y el 100%. La identificación de sus propiedades mecánicas se ha realizado basándonos en la norma UNE 14146.

This paper presents the design of an experimental setup with a reduced number of sensors for the structural health monitoring of the historical bridge of Posadas (Córdoba, Spain), designed by the eminent engineer Eduardo Torroja in 1957. The motivation of this study stems from the need for safeguarding this piece of cultural heritage. In particular, the singularity of this historical construction, a steel–concrete composite typology consisting of a concrete deck slab and inverted bowstring steel trusses, makes continuous in-service condition assessment essential for its maintenance. Nevertheless, the application of existing continuous monitoring systems to such large-scale structures entails considerable investments as well as complex signal processing algorithms. Whereby the optimization of the number of sensors and their location is of the utmost interest. In this line, this work presents the application of an Optimal Sensor Placement (OSP) methodology to tailor an experimental setup for a cost-efficient continuous monitoring of the E. Torroja’s bridge. Due to the fact that most OSP approaches are model-based, it is essential to count on a sufficiently accurate numerical model. To this aim, an extensive vibration-based operational modal analysis is first conducted with a large number of accelerometers. Afterward, a three-dimensional finite element model of the E. Torroja’s bridge is updated on the basis of the experimentally identified dynamic properties with a genetic optimization algorithm. Finally, an optimal sensor placement methodology is utilized to design an experimental setup with a limited number of sensors for long-term monitoring purposes. The results demonstrate that few sensors are needed to accurately assess the main resonant frequencies and mode shapes.

The preservation of the architectural heritage is a fundamental aspect in the cultural development of modern cities. This heritage has to be preserved and different technical analysis are usually necessary to ensure its proper preservation. Due to this fact, before performing these analyses, non-destructive techniques are usually an indispensable tool to provide information about the current structural behavior of the building. The use of ambient vibration tests is widespread as a technique to identify dynamic properties of historical constructions from a global point of view, but not to identify these dynamic properties of specific elements with a local character. In this paper, these techniques are used to characterize dynamically concrete parts of a historical building. These dynamic structural parameters identified by using the operational modal analysis method allows the adjustment of numerical models in order to obtain a more accurate estimation of the actual behavior of the structure. In this way, updated FE models can be used to assess the structural behavior of the historical building.In the present paper, the use of ambient vibration tests on the masonry roof of the Basilica of the Fourteen Holy Helpers is presented. This is a church located near the town of Bad Staffelstein near Bamberg, in Bavaria, southern Germany. The late Baroque-Rococo basilica, designed by Balthasar Neumann, was constructed between 1743 and 1772. It is dedicated to the Fourteen Holy Helpers, a group of saints venerated together in the Catholic Church, especially in Germany at the time of the Black Death.

Balthasar Neumann was a German Baroque architect with a wide experience on the design and construction of geometrically singular masonry vaults. Understanding the complex behaviour of this masonry vaults appears as a fundamental aspect to ensure its proper preservation. It is well known that historical heritage has to be preserved and different technical analysis are usually necessary to achieve it. Before performing these analyses, non-destructive techniques are usually an indispensable tool to provide information about the current structural behavior of the building. The use of ambient vibration tests and operational modal analysis method are widespread as a process to identify dynamic properties of historical constructions from a global point of view, but not to identify these dynamic properties of specific elements. In this paper, these techniques are used to characterize dynamically concrete parts of the Basilica of the Fourteen Holy Helpers and Chapel of the Würzburg Residence, specifically its roofs.

The use of Operational Modal Analysis is establishing as an acceptable tool to estimate the dynamic properties of heritage buildings as a non‐destructive technique. Through its application, mechanical properties of structural elements, as stiffness or mass, can be obtained with great accuracy. The information obtained can be used to update finite element models, however this process is complicated due to presently it is made manually. This work wants to develop a technique which expects improve the effort and the time invert in this process. The genetic algorithms are going to be used to update tow finite element models of tow patrimonial buildings, the Pavilion of Charles V and the San Jeronimo Monastery both located in Seville, in which variables like elasticity module or boundary conditions are going to be updating in order to have a real behaviour model to carry out the structural assessment of the buildings.

This paper addresses the structural safety assessment of the Chapel of the Würzburg Residence (Germany), one of the most important churches of the Central European Baroque. It was declared as World Heritage Site by UNESCO in 1981, one of its most unique and distinctive characteristics is the geometry of its complex vaults. Intersections between vaults are warped and vaults surfaces were built using only one layer of brick masonry. In this work, a nonlinear finite elements (FE) model has been developed and used to assess the structural safety of the building. In order to update the model by identifying the dynamic response of the building, experimental ambient vibration tests have been previously subsequently carried out. Operational Modal Analysis (OMA) has been used to experimentally identify both modal displacements and natural frequencies. The numerical FE model is them adjusted using genetic algorithms until its dynamic response resembles that experimentally observed, thus providing a valid model to further analyse the structural behaviour of the building. After briefly descripting the Chapel, the methodology followed to update the numerical model and the obtained results from a non-linear analysis on this over-complex vaulted structure are the main goals of the paper.

El análisis modal operacional (OMA) se ha consolidado en las últimas décadas como un método de gran interés para caracterizar los parámetros dinámicos (frecuencias naturales, modos de vibración y coeficientes de amortiguamiento modal) de todo tipo de estructuras. Los buenos resultados obtenidos, la simplicidad de aplicación y el bajo coste de su ejecución, hacen de esta técnica una herramienta muy atractiva. Presenta un especial interés la asociación de OMA al mundo de la arquitectura histórica, donde el uso de técnicas no destructivas resulta fundamental para su evaluación estructural. La aplicación de OMA antes y durante el desarrollo de un programa de rehabilitación sobre una edificación histórica, proporciona una serie de datos sobre los efectos que dicha intervención ha tenido sobre la estructura de dicha edificación. Por un lado, permite observar los cambios en los parámetros dinámicos de la estructura, haciendo estimaciones de éstos en diferentes estados de la rehabilitación, realizándose así un control de la intervención. Por otro lado, los datos obtenidos pueden usarse para calibrar y validar modelos numéricos, reduciéndose así el elevado nivel de incertidumbre que presentan los modelos de elementos finitos (EF) de este tipo de edificaciones. La calibración del modelo se refiere a la corrección de las deficiencias inherentes en el modelo de EF, haciendo coincidir los resultados de éste con los datos obtenidos experimentalmente a través de OMA. En el presente documento de investigación, tras repasar los fundamentos teóricos y el estado del arte de la aplicación de OMA sobre estructuras históricas de fábrica, se presenta la doble vertiente que ofrece dicha técnica a través de su aplicación práctica sobre una serie de casos de estudio. El Teatro Romano de Cádiz (Cádiz, España), la Capilla de la Jura (Jerez de la Frontera, España), la Iglesia de Santiago (Jerez de la Frontera, España), el Monasterio de San Jerónimo de Buenavista (Sevilla, España) y la Capilla d

La capilla de la Jura fue construida a finales del siglo XVI. Se trata de una construcción de marcado estilo gótico, situada en el lado del Evangelio del gran ábside de la iglesia de San Juan de los Caballeros. El recinto posee planta cuadrada, se levanta en cantería y se cubre con una bóveda estrellada cuyos plementos son de ladrillo. Los nervios descansan sobre columnillas suspendidas con capiteles fitomorfos. El perfil de los nervios consiste en varias molduras que terminan en un baquetón de remate plano. En el presente se pretende analizar una reciente intervención estructural que se ha llevado a cabo sobre la cubierta de la capilla de la Jura mediante un análisis basado en pruebas de vibración ambiental. Debido a la dificultad que supone evaluar correctamente los efectos de la intervención sobre este tipo de estructuras, fue necesaria la realización de diversas pruebas de vibración ambiental para poder estimar los cambios de rigideces dados en la capilla. Los datos obtenidos en las diferentes campañas experimentales fueron analizados mediante la técnica de análisis modal operacional (OMA). Dicho método es una técnica utilizada en el análisis estructural de edificaciones históricas atendiendo a varios aspectos, tales como la actualización de modelos numéricos o la monitorización continua en la valoración de la salud del edificio. De esta forma se identificaron 6 modos de vibración con sus correspondientes formas modales en un rango de frecuencia de 0 a 12 hercios. Estos datos fueron comparados y evaluados entre sí para concluir el efecto que la intervención estructural ha tenido sobre la estructura de la capilla.

Las pruebas de vibración ambiental están consolidadas desde décadas en el mundo ingenieril como uno de los principales métodos experimentales para evaluar el comportamiento dinámico de estructuras a gran escala. La excitación artificial de grandes estructuras conlleva una gran complejidad, lo que hace recurrir al análisis modal operacional (OMA) para la identificación modal de las propiedades dinámicas de la estructura. En los últimos años podemos encontrar numerosas aplicaciones de pruebas de vibración ambiental sobre construcciones históricas de fábrica. Son numerosos los factores favorables que han hecho de esta técnica una herramienta realmente útil para identificar las propiedades dinámicas de una edificación histórica. Entre ellos, el bajo coste económico que supone hacer este tipo de pruebas, la no interrupción del normal funcionamiento del edificio mientras las pruebas son realizadas y, especialmente, el hecho de ser una técnica no destructiva, factor fundamental en este tipo de construcciones. El presente estudio investiga las características dinámicas de la Iglesia de Santiago (Jerez de la Frontera), edificio de carácter gótico construido a finales del siglo XV. Tras realizar las diferentes pruebas de vibración ambiental y utilizar dos técnicas de identificación modal, seis modos de vibración fueron obtenidos en un rango de frecuencia de 0 a 10 hercios. La bondad de los resultados obtenidos fue estudiada comparando las diferencias entre las frecuencias naturales y los desplazamientos modales obtenidos. Se concluye la idoneidad del método presentado, como técnica no destructiva, para caracterizar dinámicamente edificaciones históricas de fábrica.

Nowadays, the preservation of the architectural heritage is a fundamental aspect in the cultural development of modern cities. This heritage has to be preserved and different technical analysis are usually necessary to ensure its proper preservation. The main problem is that the greatest difficulty for the analytical analysis of kind of buildings is the high level of uncertainty associated with many factors. For example, slight modifications of the geometry or the mechanical properties of the structural materials can be the cause of great differences between the results obtained from an analytical analysis and others estimated experimentally. Due to this fact, before performing these analysis, non-destructive techniques are usually an indispensable tool to provide information about the current geometry and the structural behaviour of the building. Thus, the use of photogrammetric techniques and ambient vibration tests allows the right definition of the current geometry and the dynamic characterization of the building, respectively.

One of the first difficulties that can be detected in finite element models of historical buildings is the high level of uncertainty associated with many factors affecting the actual behaviour of the structure. Often the inaccuracies in this model will arise because of poorly known boundary conditions, unknown material properties or simplification in the modelling. These uncertainties in the modelling process cause the predicted dynamics of a structure to be different from the measured dynamics of the real structure. If accurate measured data is available, then this data could be used to improve the numerical model in general and some uncertain parameters of the model in particular. Thus, among the Operational Modal Analysis method, the finite element model updating from the dynamic structural parameters identified experimentally, allows the adjustment of these models in order to obtain a more accurate estimation of behaviour of the structure.

This paper presents the dynamic characterization of a group of historical buildings located over the Roman Theatre of Cadiz (Spain), a piece of heritage that has been buried for centuries under the historical town. In 2010, an intervention began in order to excavate it, while respecting the buildings over it. The control of this intervention is being done by means of topographic control points and ambient vibration tests. On the basis of the results obtained from the dynamic tests, a finite element model was updated and subsequently used to check the current works and foresee the final behaviour of the complex. A brief description of the Roman theatre and the works to recover it, the methodology followed to control such works and the results obtained are the main goals of this paper.

One of the main difficulties that can be detected in a historical building structural analysis is the high level of uncertainty associated with many factors affecting the behavior of the structure. Slight modifications of the mechanical properties of the structural materials, the soil-structure interaction or even the building construction process may be the cause of high changes between the results obtained from a numerical analysis and others estimated experimentally. Among the non-destructive techniques, the finite element model updating from the dynamic modal parameters identified experimentally, allows the adjustment of these models in order to obtain a more accurate estimation of behaviour of the structure. In the present paper, the implementation of this technique on the Chapel of the Würzburg Residence (Germany), one of the most important churches of the Central European Baroque has been presented. The experimental modal parameters have been estimated from the operational modal analysis of the signals measured at different points of the structure during an ambient vibration test. The correlation between the numerical and experimental modal parameters after the updating process is adequate.

El Teatro Romano de Cádiz (España) es parte de la herencia romana que ha permanecido oculta durante siglos bajo el casco histórico de la ciudad. Se trata del teatro romano más antiguo y de mayores dimensiones localizado en España. En el año 2010, se inició una intervención con el fin de descubrirlo. La intervención consiste en la construcción de una serie de bóvedas de hormigón bajo los edificios construidos sobre el teatro aplicando la técnica de la inyección armada. El control de esta intervención se está realizando por medio de dos técnicas: control topográfico y Análisis Modal Operacional. La metodología seguida para el control de la intervención en el área del teatro romano y los resultados obtenidos de la misma son los principales objetivos del presente artículo., The Roman Theatre of Cadiz (Spain) is a piece of heritage that has been buried for centuries under the historical town. It is the oldest and biggest Roman theatre in Spain. In 2010, an intervention began in order to dig it up but respecting the monumental landmarks over it. The intervention consisted on the construction of some vaults under the blocks by grout injection. The control of this intervention is being done by two different techniques: topographic control points and Operational Modal Analysis. The methodology that has been followed to control the intervention on this area and the obtained results are the main goals of this paper.

Una de las primeras dificultades que se plantean a la hora de analizar un edificio histórico es el gran nivel de incertidumbre asociado a multitud de factores condicionantes del comportamiento de la estructura. Pequeñas modificaciones de las propiedades mecánicas estimadas de los materiales constituyentes, los fenómenos de interacción suelo-estructura o incluso el propio proceso constructivo pueden ser causantes de grandes variaciones entre los resultados obtenidos a partir de un análisis numérico y los estimados de forma experimental. Dentro de las técnicas no destructivas, la actualización de modelos de elementos finitos, a partir de los parámetros dinámicos de la estructura identificados experimentalmente, permite una calibración de dichos modelos al objeto de obtener una estimación más precisa del comportamiento de la estructura. En el presente artículo se describe la aplicación de dicha técnica sobre la capilla del Palacio de Würzburg (Alemania), una de las construcciones más importantes del Barroco Centroeuropeo., One of the first difficulties that can be detected in a historical building structural analysis is the high level of uncertainty associated with many factors affecting the behaviour of the structure. Slight modifications of the mechanical properties of the structural materials, the soil-structure interaction or even the building construction process may be the cause of high changes between the results obtained from a numerical analysis and others estimated experimentally. Among the non-destructive techniques, the finite element model updating from the dynamic structural parameters identified experimentally, allows the adjustment of these models in order to obtain a more accurate estimation of behaviour of the structure. In the present paper, the implementation of this technique on the Chapel of the Würzburg Residence (Germany), one of the most important churches of the Central European Baroque, is described.

El monasterio de San Jerónimo de Buenavista en Sevilla fue construido en 1414. Desde entonces ha sufrido grandes daños, manteniéndose en la actualidad solamente el claustro principal. Este último incluso sufrió daños de consideración ocasionados por el terremoto de marzo de 1969. El claustro de dos plantas presenta arcos de medio punto en planta baja y escarzanos en segunda. Tres de las cuatro fachadas no mantienen en segunda planta las bóvedas correspondientes. La arquería y las bóvedas están ejecutadas en piedra y el muro trasero mediante fábrica de ladrillo y tapial. En este trabajo se pretende analizar estructuralmente el único elemento que queda en pie, el claustro principal, mediante un análisis basado en el método de los elementos finitos (MEF). Debido a la dificultad de identificar correctamente la rigidez real que presenta en la actualidad dicho claustro, se van a utilizar técnicas de análisis modal operacional (OMA) para poder calibrar el modelo inicial de (MEF) y así predecir el comportamiento estructural ante cualquier acción a la que pueda estar sometida, principalmente en la actualidad las debidas a la intervención que se está realizando sobre dicho claustro y su entorno.

The use of Operational Modal Analysis is establishing as an acceptable tool for the update of numerical models. Through its application, mechanical properties of structural elements, as stiffness or mass, can be obtained with great accuracy. The analysis of the current structural state of the Monastery of San Jerónimo, an important piece of heritage located in Seville (Spain), is presented in this paper. The monastery dates from the XV century. The cloister has been analysed by OMA in order to update a FE model, to subsequently carry out the structural assessment of the Monastery.

El presente artículo expone la caracterización dinámica de un grupo de edificios situados sobre el Teatro Romano de Cádiz a través de pruebas de vibración ambiental. Con los datos obtenidos de estas pruebas se calibraron los modelos de elementos finitos (EF) necesarios para realizar el control de las obras que se están ejecutando actualmente en esta área y predecir el efecto final de las mismas sobre el conjunto estructural.