Search

Masonry buildings of historical centres are usually organized within aggregates, whose structural performance against seismic actions is challenging to predict and constitutes still an open issue. The SERA—AIMS (Seismic Testing of Adjacent Interacting Masonry Structures) project was developed to provide additional experimental data by testing a half-scale, two-unit stone masonry aggregate subjected to two horizontal components of dynamic excitation. In this context, this paper investigates the reliability of the modelling approach and the assumptions adopted to generate a three-dimensional continuum finite element model. The work involves two stages, namely a blind pre-diction and a post-diction phase, and proposes a series of simulation analyses including a strategy to shorten the actual records and save computation costs. The study was performed to investigate the extent of uncertainty in modelling for such masonry aggregates in relation to the experimental outcomes. Pre-diction results were proven to be not accurate in terms of predicted displacements and damage patterns. The upgrades introduced for the post-diction analyses, including the calibration of the elastic modulus and the introduction of a non-linear interface between the two units, allowed to improve the outcomes, with reasonable results in terms of predicted base shear force, displacements along Y-direction and damage pattern for the non-linear stage. The overall approach showed to be appropriate for the structural analysis of existing masonry aggregates, but the accurate modelling of this type of structure remains challenging due to the high level of uncertainties. [ABSTRACT FROM AUTHOR]

Throughout history, the architecture of worship structures has been shaped based on different cultures and belief systems during the Roman, Seljuk, Anatolian Principalities, and Ottoman periods. Additionally, it is understood that the sociocultural and ritual structure in which the worship place is built plays a significant role in church architecture. In province of Ordu, rich in historical and cultural heritage, historical structures outside the city center have not been well preserved. In recent years, neglected historical structures have been restored through various methods with public investments, aiming to reintegrate them into urban life. Through chemical and mineralogical (by microscopy) examinations aimed at determining the types of historical structural materials used for this purpose, the preservation of historical structures in Ordu province and their transfer to future generations is targeted. Church structures, holding a distinct significance in the region's history, exhibit various characteristics in terms of location, climate, and sociocultural and ritual aspects in the Black Sea region. In this regard, the restoration of the historical Taşbaşı Church in the Altınordu district of Ordu province has been carried out considering scientific techniques and methods, serving as a guide for similar studies in the region in terms of laboratory analysis, studies, planning, project development, and implementation stages. [ABSTRACT FROM AUTHOR]

David Hume's historical thought was shaped before he even began writing the History of Great Britain in 1752. This article shows how Hume developed his historical thought in an attempt to combine two historical structures: the natural-jurisprudential conjectural history of the Treatise of Human Nature and the early eighteenthcentury historical narratives of modern Europe that featured in his Essays. The Treatise's conjectural history used the developmental categories "rude" and "civilised" to explain the origins of justice, government and the moral sentiment. The narratives of modern Europe, in contrast, revolved around the historical categories "ancient" and "modern." Hume's historical thought was shaped by the attempt to merge those two structures into a single, coherent structure. The critical question concerned the relation between the ancient and the modern: was modern Europe merely a "revival" of classical antiquity? Or did it have new, "post-ancient" dimensions? The article shows how Hume gradually distanced classical antiquity from modern Europe, thereby creating space for exclusively modern concepts such as "civilised monarchies" and the narrative of modern civilisation that structured his History of England (1754-1762). The paper concludes by suggesting that this structure defined Enlightenment philosophical history, not just Hume's version of it. [ABSTRACT FROM AUTHOR]

A temporary monitoring system was installed on the 175-year-old historical Széchenyi Chain Bridge during its reconstruction. The bridge is in the downtown area in the capital city of Hungary and plays a significant role in the city life of Budapest. Six-month-long measurements were conducted during the reconstruction process of the bridge, yielding crucial insights into the structural behaviour of the historical structure. The measurement results were evaluated; the findings encompass the rotation capacity of the pins between the chain elements and the structural response to temperature changes. This information helped the decision-making between 2021 and 2023 by the designers and construction company during the reconstruction. For instance, daily temperature fluctuations resulted in increased bending moments in the chain elements, rising up to 158% compared to the values observed during a proof load test in 2018. Furthermore, the measurements reveal an approximate 42% increase in normal forces compared to the proof load test, which highlights the high sensitivity of chain bridges to temperature fluctuations, where geometric stiffness plays a crucial role. Reconstruction, namely reducing self-weight, notably intensifies the impact on normal forces and bending moments. These outcomes strongly emphasize the dominance of the dead load and self-weight in the case of chain bridges. [ABSTRACT FROM AUTHOR]

Throughout history, the architecture of worship structures has been shaped based on different cultures and belief systems during the Roman, Seljuk, Anatolian Principalities, and Ottoman periods. Additionally, it is understood that the sociocultural and ritual structure in which the worship place is built plays a significant role in church architecture. In province of Ordu, rich in historical and cultural heritage, historical structures outside the city center have not been well preserved. In recent years, neglected historical structures have been restored through various methods with public investments, aiming to reintegrate them into urban life. Through chemical and mineralogical (by microscopy) examinations aimed at determining the types of historical structural materials used for this purpose, the preservation of historical structures in Ordu province and their transfer to future generations is targeted. Church structures, holding a distinct significance in the region’s history, exhibit various characteristics in terms of location, climate, and sociocultural and ritual aspects in the Black Sea region. In this regard, the restoration of the historical Taşbaşı Church in the Altınordu district of Ordu province has been carried out considering scientific techniques and methods, serving as a guide for similar studies in the region in terms of laboratory analysis, studies, planning, project development, and implementation stages.

This paper presents the historical development of the vertical extensions of unreinforced masonry buildings in the Eixample district of Barcelona and their impact on the seismic behaviour. Existing masonry buildings of Eixample present significant seismic risk because, despite the low to moderate seismic hazard of Barcelona, they show a marked vulnerability given their average height of six storeys and the substantial slenderness of the walls. Between the end of the 19th century and the beginning of the 20th century, the vertical extensions, known as remuntes in Catalan, were a common solution to the increasing demographic demand of the city. In their majority, these vertical extensions add a structural irregularity that represents a potential vulnerability factor not yet investigated. The present study focuses on Eixample's remuntes, including their historical development, the description of their structural features, and the identification of their most representative configurations in the existing building stock. A seismic analysis based on the Finite Element Method is presented on a reference model without extensions and three others with the most recurrent configurations of remuntes. The seismic response is investigated through pushover analysis. The results provide a better understanding of the negative impact of the vertical extensions on the seismic performance. [ABSTRACT FROM AUTHOR]

Two Ottoman period mansions in central Greece featuring timber-framed masonry walls and exhibiting many similarities in their construction are examined and several defining attributes are traced, connecting their structural system with that of similar buildings in mainland Greece. These buildings consist of a stone masonry ground floor, while the upper storey construction is a combination of stone and timber-framed masonry. The materials typically incorporated in such structures are presented. Details are given on the connections of timber elements. These buildings were constructed in seismically active areas, and have frequently been subject to earthquake strong motions, with the observed damages presented herein. The purpose of this investigation is to understand the load-bearing system of the mansions and its response under earthquake actions. The findings can later be used for further research of these structures. [ABSTRACT FROM AUTHOR]

The fundamental frequency plays a primary role in the dynamic assessment of Cultural Heritage towers. Local and global features may impact its value: geometric, material features, interaction with the soil and adjacent buildings, aging, the construction phase, and repairs. A database is assembled to study the relationship between the fundamental frequency and the slender masonry structure features. Empirical and physics-based approaches were developed to assess the fundamental frequency from different sources of information. A Rayleigh–Ritz approach is proposed and compared with a 3D finite element model. A sensitivity analysis is then performed to quantify the contribution of each feature. As expected, it is shown that the height of the tower contributes the most to the fundamental frequency. The other tower features have a second-order impact on both the fundamental frequency and the mode shape. A comparison between the different approaches shows that the Rayleigh–Ritz drastically minimizes the difference between numerical and experimental frequencies when all information is available. Empirical relations are a good compromise when less information is available. [ABSTRACT FROM AUTHOR]

A temporary monitoring system was installed on the 175-year-old historical Széchenyi Chain Bridge during its reconstruction. The bridge is in the downtown area in the capital city of Hungary and plays a significant role in the city life of Budapest. Six-month-long measurements were conducted during the reconstruction process of the bridge, yielding crucial insights into the structural behaviour of the historical structure. The measurement results were evaluated; the findings encompass the rotation capacity of the pins between the chain elements and the structural response to temperature changes. This information helped the decision-making between 2021 and 2023 by the designers and construction company during the reconstruction. For instance, daily temperature fluctuations resulted in increased bending moments in the chain elements, rising up to 158% compared to the values observed during a proof load test in 2018. Furthermore, the measurements reveal an approximate 42% increase in normal forces compared to the proof load test, which highlights the high sensitivity of chain bridges to temperature fluctuations, where geometric stiffness plays a crucial role. Reconstruction, namely reducing self-weight, notably intensifies the impact on normal forces and bending moments. These outcomes strongly emphasize the dominance of the dead load and self-weight in the case of chain bridges.

From chronological, constructive and heritage conservation points of view the Roman bridge of Alcántara (Spain) is an exceptional bridge. Erected around 103 AD on the Tagus River, it is still in use today for road traffic. Recently, the construction of a new bridge 200 meters upstream from the old one, intended to relegate the old bridge to pedestrian use, has been promoted. The examination of the new project and its long administrative procedure, as well as the analysis of the characteristics of the Roman bridge and its surroundings, both from a territorial and social point of view, provide a foothold to assess the new bridge according to a broad conception of heritage conservation. The objective of this work is to underline the unique history of the conservation of this bridge and, while presenting proposed solution for the new bridge, to highlight the patrimonial conditions that have been taken into account. The conclusion is that the administrative procedure followed in order to choose the solution and the project for the new Alcántara bridge are not adequate to the characteristics of such an outstanding monument. [ABSTRACT FROM AUTHOR]

This paper presents a discrete macro‐element accounting for P‐Delta effects to describe the rocking response of masonry walls subjected to out‐of‐plane (OOP) loadings. Both constitutive and geometric nonlinearities are considered within the discrete macro‐element method (DMEM), which is a modeling approach characterized by a very low computational cost compared to traditional distinct element method (DEM) and detailed finite element (FEM) strategies. OOP failure mechanisms are the main cause of severe damage for unreinforced masonry (URM) buildings, subjected to seismic actions. These mechanisms are generally activated by low seismic excitation and displacements. However, after their activation, they can evolve towards large displacements related to rigid‐block‐like kinematics that strongly affects the nonlinear mechanical response. Therefore, geometric nonlinearities, often ignored, should be included in the analyses. A new simplified, still accurate P‐Delta formulation is presented, according to which the global equilibrium is imposed by referring to the undeformed system configuration, avoiding assembling the geometric stiffness matrix. Namely, the system load vector is updated at each step of the analysis, accounting for the additional moments generated by the in‐plane compression forces acting on the macro‐elements in the deformed configuration. The proposed model is validated against closed‐form analytical solutions of rigid‐block benchmarks in large displacements and the results of experimental tests already available in the literature. In addition, extensive parametric analyses are performed to investigate the role of different mechanical and geometric parameters characterizing the ultimate non‐linear response of masonry walls subjected to horizontal forces. The results show how the proposed model, including P‐Delta effects, accurately predicts the non‐linear rocking response of masonry walls until the attainment of the unstable configuration. [ABSTRACT FROM AUTHOR]

Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than 600 historic structures, which require extensive studies to sustain their cultural, religious, and economic values. The main aim of this paper is to undertake dynamic investigation tests for the dome of Fatima Khatun, a historic mausoleum in Historic Cairo dating back to the 13th century and consisting of mainly bricks and stones. The challenge was that the structure was difficult to access, and only a small portion of the top was accessible for the attachment of accelerometers. Current dynamic identification procedures typically adopt methods in which the sensors are arranged at optimal locations and permit direct assessment of the natural frequencies, mode shapes, and damping ratios of a structure. Approaches that allow for the evaluation of dynamic response for structures with limited accessibility are lacking. To this end, in addition to in situ dynamic investigation tests, a numerical model was created based on available architectural, structural, and material documentation to obtain detailed insight into the dominant modes of vibration. The free vibration analysis of the numerical model identified the dynamic properties of the structure using reasonable assumptions on boundary conditions. System identification, which was carried out using in situ dynamic investigation tests and input from modelling, captured three experimental natural frequencies of the structure with their mode shapes and damping ratios. The approach proposed in this study informs and directs structural restoration for the mausoleum and can be used for other heritage structures located in congested historic sites. [ABSTRACT FROM AUTHOR]

This article discusses the problems and technical issues related to the conservation and rehabilitation of historic wooden structures. Showing the history of wooden construction in Europe and Poland, it analyzes the technical solutions used for the timber structure of buildings. The author highlights the leading technical and conservation issues arising from the principles of conservation of wooden heritage buildings, taking into account the role, importance, and proper implementation of diagnostics preceding conservation engineering activities. The article discusses interdisciplinary diagnostics developed by the author, an original method for assessing the revitalization capability of a historical building, which analyzes non-technical issues, including those relevant to conservation, in addition to the technical aspects of assessing the technical condition of a building. Based on engineering practice, problems and technical issues that often occur in the conservation process of wooden buildings, as well as in the broader process of their revitalization, are presented. They concern various engineering activities that must be implemented in this process according to the principles discussed. [ABSTRACT FROM AUTHOR]

The fundamental frequency plays a primary role in the dynamic assessment of Cultural Heritage towers. Local and global features may impact its value: geometric, material features, interaction with the soil and adjacent buildings, aging, the construction phase, and repairs. A database is assembled to study the relationship between the fundamental frequency and the slender masonry structure features. Empirical and physics-based approaches were developed to assess the fundamental frequency from different sources of information. A Rayleigh–Ritz approach is proposed and compared with a 3D finite element model. A sensitivity analysis is then performed to quantify the contribution of each feature. As expected, it is shown that the height of the tower contributes the most to the fundamental frequency. The other tower features have a second-order impact on both the fundamental frequency and the mode shape. A comparison between the different approaches shows that the Rayleigh–Ritz drastically minimizes the difference between numerical and experimental frequencies when all information is available. Empirical relations are a good compromise when less information is available.

The paper presents the virtual reconstruction and analysis of the project for the Cathedral of Villahermosa in Tabasco (Mexico), designed by Félix Candela in 1960 in collaboration with Jorge Creel and Juan José Díaz. With 9-meter cantilevers supported by a single column and a height of more than 35 meters, the inverted umbrellas designed for the Cathedral would have been the tallest ever built by Candela using this structural system.The project presents a variation of the traditional hyperbolic-paraboloid (hypar) umbrellas widely used by Candela in Mexico during the 50s and 60s. A parabolic discontinuity is introduced in each fragment of the surfaces, resulting in a structure formed by eight different hypars. This is not the first project where Candela used this type of variation, however, by modifying the direction of the generators and increasing the height of the hypars, it was possible to improve the curvature of the structure and reduce the deflections that appeared in previous constructions.The virtual reconstruction of the project has been developed using a procedural non-destructive 3D model. The algorithm enables to modify the geometry and introduce different iterations in Grasshopper and Houdini. It has been linked with Unreal Engine, allowing to render the final project and its variations in real time and exporting the scenes to Virtual Reality. The procedure avoids the need of exporting multiple iterations -as they can be generated inside the render engine- as well as the loss of precision associated when converting NURBS to polygonal meshes in curved surfaces, using a discretization process.DOI: https://doi.org/10.20365/disegnarecon.27.2021.10

The dynamic response of freestanding structures is poorly predicted due to known sensitivity to geometry and input motion. To further elucidate the salient features of this dynamic response, the aim of this study is to investigate the response of complex freestanding systems under real-world conditions. Two statue-pedestal systems that overturned during the 2014 South Napa Earthquake are employed in this study. The results of the numerical simulation are analyzed in comparison to the observed response which unlocks key details regarding the impact of soil at the base, contact stiffness, statue orientation, and ground motion directionality. [ABSTRACT FROM AUTHOR]

Copyright of Online Journal of Art & Design is the property of Online Journal of Art & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The vigorous debate on global land grabbing within Critical Agrarian Studies contrasts with the incipient analyses from International Political Economy (IPE). This divergence has overshadowed the multi-scalar nature of the power relations that shape land governance, and consequently its effects on land grabbing. For this reason, this paper provides a critical theoretical model of land governance based on Robert Cox’s historical structures approach to understand the causes of land grabbing in Latin American countries. It is argued that this model renders visible the articulation of local and global processes driving land grabbing because it foregrounds the power relations at multiple scales that shape decisions on land access, use and control, as well as the conflicts inherent to them. This demonstrates that, on the one hand, land governance structures in Latin America play a hegemonic role since they express and develop the global agricultural model that promotes land grabbing. On the other hand, social resistance highlights that land governance simultaneously possesses a potential for change. As a result, knowledge about land grabbing is enhanced through a dialogue between the two fields of study.

Kültürel mirasımızın parçası olan tarihi yapıları korumamız ve yaşatmamız gerekmektedir. Bunun için tarihi yapıların davranışının bilinmesi ve analiz edilmesi gerekmektedir. Yapılan çalışmada, Gaziantep’te bulunan 18. yy yapılan Tahtani (Leylek) Caminin yapısal durumu incelenmiştir. Bu cami üzerinde daha önceden güçlendirme çalışmaları yapılmıştır. Yapının mevcut durumu incelendiğinde caminin beden duvarlarında ve tonozlarda bulunan yapısal hasarlar belirlenmiştir. Çalışmada 3 boyutlu sayısal modeli oluşturmak için sonlu elemanlar yöntemini (SEY) esas alan LUSAS yazılımından yararlanılmıştır. Sonlu elemanlar yöntemi ile caminin mevcut durumu (MD) ve restorasyon sonrası durumu (RD) analiz edilmiştir. Çalışmada caminin yapısal hasarlarının nedenleri belirlenerek camide daha önce yapılan restorasyon hatalarının düzeltilmesine yönelik önerilerde bulunulmuştur. Tahtani Camisinin onarım ve güçlendirilmesi için yığma birimlerde meydana gelen hasarlarda yeniden örme uygulaması, beden duvarı derzlerindeki ayrılmalarda enjeksiyon uygulaması, bütün sütunlar arasında da gergi demiri uygulamasının yapılması önerilmiştir.

Historical buildings are types of buildings that reflect the culture, history, economic and social characteristics, beliefs of the period they are in. Dome type structures, which are among these building types, are curvilinear cover systems made to pass large openings. In order to transfer historical structures to future generations, structures should be protected and their structural behavior should be well known. In this study, an experimental study was carried out to examine the strengthening of dome structures by using clamps. Firstly, the behavior of the 2 m diameter and 1 m high octagonal pulley dome under vertical load was investigated. When the dome reached its load-bearing capacity, some cracks occurred on the dome. These damages were repaired by using clamp connectors. The dome strengthened with clamps was tested again under vertical load. The testing results of the reference and the clamp-reinforced domes are compared. As a result of the study, it has been determined that the clamp-applied strengthening method, which is frequently used in the repair and strengthening of dome structures, does not increase the bearing capacity. [ABSTRACT FROM AUTHOR]

The vigorous debate on global land grabbing within Critical Agrarian Studies contrasts with the incipient analyses from International Political Economy (IPE). This divergence has over-shadowed the multi-scalar nature of the power relations that shape land governance, and consequently its effects on land grabbing. For this reason, this paper provides a critical theoretical model of land governance based on Robert Cox's historical structures approach to understand the causes of land grabbing in Latin American countries. It is argued that this model renders visible the articulation of local and global processes driving land grabbing because it foregrounds the power relations at multiple scales that shape decisions on land access, use and control, as well as the conflicts inherent to them. This demonstrates that, on the one hand, land governance structures in Latin America play a hegemonic role since they express and develop the global agricultural model that promotes land grabbing. On the other hand, social resistance highlights that land governance simultaneously possesses a potential for change. As a result, knowledge about land grabbing is enhanced through a dialogue between the two fields of study. [ABSTRACT FROM AUTHOR]

Historical structures are cultural heritage constituents that convey the traces and characteristic features of civilizations to the present days. One of these structures, which are among the monumental artefacts, are historical bridges. To protect historical buildings, 3D photogrammetric documentation of these structures, detailed determination of geometric and material properties and performing computer-aided structural analysis using appropriate modelling techniques are very important. The aim of this study is to present an effective, reliable, and fast multidisciplinary approach for the analysis of historical masonry bridges. The aforementioned approach is presented as an example for the behavior of the recently restored historical Ayvalıkemer (Sillyon) masonry arch bridge under possible loadings. Terrestrial laser scanning (TLS) was used to determine the bridge geometry with high accuracy. The point cloud data obtained from TLS was simplified and a three-dimensional CAD based solid model of the structure was created. This solid body has been formed the basis of the macro model for structural analysis. CDP material model was used to describe the inelastic behavior of homogenized structure. Thus, an analysis was carried out which presents the structural behavior of a historical bridge with high accuracy and reliability. [ABSTRACT FROM AUTHOR]

Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than 600 historic structures, which require extensive studies to sustain their cultural, religious, and economic values. The main aim of this paper is to undertake dynamic investigation tests for the dome of Fatima Khatun, a historic mausoleum in Historic Cairo dating back to the 13th century and consisting of mainly bricks and stones. The challenge was that the structure was difficult to access, and only a small portion of the top was accessible for the attachment of accelerometers. Current dynamic identification procedures typically adopt methods in which the sensors are arranged at optimal locations and permit direct assessment of the natural frequencies, mode shapes, and damping ratios of a structure. Approaches that allow for the evaluation of dynamic response for structures with limited accessibility are lacking. To this end, in addition to in situ dynamic investigation tests, a numerical model was created based on available architectural, structural, and material documentation to obtain detailed insight into the dominant modes of vibration. The free vibration analysis of the numerical model identified the dynamic properties of the structure using reasonable assumptions on boundary conditions. System identification, which was carried out using in situ dynamic investigation tests and input from modelling, captured three experimental natural frequencies of the structure with their mode shapes and damping ratios. The approach proposed in this study informs and directs structural restoration for the mausoleum and can be used for other heritage structures located in congested historic sites.

Historical buildings are an integral part of cultural heritage all over the world and are structures that carry the traces of the past to the present, together with the universal values they have. Although historical buildings, which generally have a masonry bearing system, have a better seismic performance compared to reinforced concrete structures, it is understood that some of these structures have suffered serious structural damage in some destructive earthquakes. Although many studies have been conducted to determine the seismic performance of historical buildings, there is no method that has been determined with strict lines to evaluate the performance of these structures. Within the scope of this study, a simplified method based on displacement was emphasized in order to determine the seismic performance of historical buildings and the seismic performance of historical Kaya Çelebi Mosque, which was damaged after the 2011 Van earthquake, was examined using this method. [ABSTRACT FROM AUTHOR]

This study investigated the mineralogical, chemical, physical, mechanical, durability–hygrothermal, thermal shock properties, and economic aspects of the Kandira stone, one of the well-known natural building stones, commonly used in many historical structures in the Marmara and Thrace regions. Especially, it has been preferred to Malta stone in historical structures in Istanbul due to economic reasons at the beginning of the 1900s. A similar appearance and lithology with Malta stone and closeness of the Kandıra stone to İstanbul made it attractive to be used as natural building stone in historical monuments and new structures. The mean physico-mechanical properties of Kandira stone yielded 2.24 g/cm3 apparent density, 2.72 specific gravity, 19.21% total porosity, 5.8% water absorption by weight, 48 MPa compressive strength, 11.4 MPa bending strength. In terms of durability properties, Kandira stone has high resistance to aging by CaCl salt mist and no or low resistance to SO2 aging in a humid environment. Also, the freeze–thaw test of Kandira stone yielded an exceptionally low mass loss (0.11%) indicating that the stone is resistant to freeze–thaw effect. Thermal shock tests indicated that Kandira stone is mainly resistant to thermal shock cycles. Economically, the calculated probable reserve of Kandira stone resulted in 40.8 × 106 tons of material and the potential economic value based on the probable reserve is calculated around 54.672 × 109 TL (approximately €7.2B). In conclusion, this study defined the petrographic, geomechanical, durability–hygrothermal and thermal shock properties essential for the use of Kandira stone as building stone and restoration material. [ABSTRACT FROM AUTHOR]

Reliable estimation of seismic stability of structures built in seismically active regions is an objective that requires a complex investigation and different types of activities. For historical structures and monuments, this requirement is even more essential, because many of them represent unique heritage structures. In-situ testing of a monument for defining dynamic characteristics and seismic testing of scaled models represent the recommended activities to be considered as mandatory. Shake table testing of a scaled monument model provides valuable information about its seismic stability – weak parts and development of failure mechanism – as well as the crucial points of the structure that should be considered when designing the health monitoring system. This paper presents the results obtained by the shake table testing of scaled models of two historical masonry structures: the Old Bridge in Mostar and the ancient Protiron structure in Split. The monitored seismic response presented herein by the measured accelerations, relative and absolute displacements, and strains, as well as the damage identification during the shake table tests, provided essential information about their seismic stability, failure mechanism, and weak points. The obtained results have been used for verification of the analytical models for these two monuments, while the prospective of the conclusions derived from the tests has a possible implementation in planning their health monitoring system. [ABSTRACT FROM AUTHOR]

The Marcus Aurelius Column has been a historical seismometer in Rome since its construction. Most of the seismic events of the past had effects on it. Therefore, the preservation of this monument is of fundamental importance for at least two reasons. First of all, to extend as much as possible its life time, in order to allow enjoying the sight to future generations. Then, the knowledge of these column characteristics will allow to improve the interpretation of historical documents on seismic event in Rome and to continue using it as historical seismometer in the Eternal City. In this paper, the last experimental vibrational analysis carried out on the Column is shown. Twenty-four velocimeter sensors, connected to a single acquisition unit, were used. Both time and frequency domain analysis were performed. [ABSTRACT FROM AUTHOR]

Since the early ages, people have used masonry material units such as stone, brick and adobes to make areas for sheltering. The problems on historical structures caused by great damages arising from earthquake, fire, and soil problems, bring about physical and chemical deterioration. These damages are generally due to low shear and tensile stresses in masonry walls. In order to overcome this weakness, clamp and dowels are often used as connection units in many historical buildings. The moving of the structural system with these elements together raises the ductile behavior of the whole structure. In this study, the distance between the edge of the stone and immersion point of clamps was taken into account as variant parameter and the influence of the clamps on the shear strength of the masonry walls are investigated. The LUSAS software based on the finite element method (FEM) are used to create a 3D numerical model. In the light of the results obtained by computer analyses, the optimum distance between the edge of the stone and the immersion points are examined and the effects of those on the stone units are comparatively illustrated. [ABSTRACT FROM AUTHOR]

Throughout history, people have built many masonry structures to meet the need for shelter. Masonry structures has taken heavy damage due to natural disasters such as earthquakes, floods, wind. The main reason is that it has low tensile strength of stone masonry structures. Various connectors have been used to increase tensile strength of the masonry structure in the history. Although these connectors were manufactured from the first wood material and then they continued to be made from metal materials with the development of technology. In this study, the effects of the clamps used as metal connection elements on the behavior of the masonry stone blocks were investigated by experimental methods. In the experimental study, immersion depth of clamps on the masonry stone block are taken into consideration as a variable. It is almost no studies in the literature on this topic and the study is aimed to overcome these short comings of the literature. [ABSTRACT FROM AUTHOR]

The non-smooth contact dynamics method was selected to investigate the damage occurred to typical masonry churches (namely Apennine churches) belonging to Central Italy areas affected by the seismic activity started in 2016. The investigated buildings show discontinuous dynamics since the optioned method gave the chance to properly model the temples as multi rigid body systems using the Signorini's impenetrability condition and the dry-friction Coulomb's law, achieving a thoughtful response to ground seismic solicitations. The results provided by the assessment grant an overview of the most common damages and failure mechanisms, giving the guidelines to restoration projects that fully respond to structural needs. [ABSTRACT FROM AUTHOR]

Clay brick is the most common construction material used in the historical buildings of Diyarbakır (Turkey). Many clay brick manufacturing workshops and numerous brick masters have emerged. Diyarbakir currently has two clay brick workshops that face the problem of being closed down. Therefore, manufacturing of clay brick by traditional methods may be forgotten in Diyarbakir. This study investigates the manufacturing phases of traditional clay bricks in Diyarbakir׳s local workshops, which have not been documented. The manufacturing phases of the clay bricks in Diyarbakır were examined for the first time based on in-situ observations, investigations, and interviews. The research indicated the general phases of clay brick manufacturing. Raw materials are first prepared, formed, and dried. The firing of clay bricks is then performed through hacking, heating, burning, cooling, and de-hacking. The clay bricks are finally packaged and dispatched. The traditional manufacturing of clay brick methods in Diyarbakır is similar in many regions of the world. The clay bricks are currently and extensively used in the restoration of historic structures. Therefore, their production must be continuous.

This paper presents an assessment of the capacity and enhancement of the seismic performance of a historical masonry structure in Plomari, a town on the south coast of Lesbos island in Greece. Owing to uncertainties regarding the properties of the material and the effectiveness of the members in providing lateral resistance, the study was particularly challenging. In addition, the fact that the structure consisted of a variety of structural element types, e.g., unreinforced masonry from natural stones, timber-framed masonry (with burned clay masonry units), and timber girders, while lacking horizontal diaphragms, introduced complexities to the response of the structure in both directions. In the design of the retrofit, the need to preserve the building's architectural and historical value by minimizing interventions posed several problems. To solve them, conventional as well as state-of-the-art strengthening methods are proposed. Moreover, the procedures of these methods are in accordance with the Greek seismic design code of 1959 and European standards (Eurocodes) related to earthquake-resistant masonry as well as guidelines for the design of timber and reinforced concrete. Seismic analyses of the structure were carried out with two different methods (statically applied load and time history analysis) for comparison. The results verify the improvement in its behavior in response to earthquakes as a result of the proposed strengthening methods.

• Experimental characterization of stone masonry joints made of as built materials. • Stiffness parameters were obtained for both dry and mortar stone masonry joints. • Bore-hole dilatometer and Menard pressuremeter tests on masonry infill material. • Oedometric and triaxial test results were obtained for masonry infill material. • Stiffness data for original infill material was made available for numerical models. The assessment of historical structures is a broad issue likely to comprise lab or in-situ testing at the structure, component or material levels, whenever relevant characterization of mechanical and physical properties is required. The material characterization of historical structures, particularly stone masonry ones as addressed herein, involve testing the constituent materials and their interfaces, namely stone blocks, interface joints (either dry or filled with mortar) and infill material. Besides stone, for which standard testing procedures are well established, interface joints and infill material testing are challenging issues. In such context, this paper reports a summary of the authors experience on characterizing materials, and respective interfaces, of historical constructions, aiming at providing input parameters' data for numerical simulations which are deemed useful for the scientific/technical community dealing with analysis of historical structures. The main focus of the paper is on stone masonry joints' testing and on infill material characterization by in-situ or lab tests. The reported experimental activities (e.g. borehole drilling and core sampling) can be considered as minor intrusive/destructive for the global constructions, because they are very localized and can easily repairable. [ABSTRACT FROM AUTHOR]

This research focuses on estimating the axial force of historical metal tie-rods by means of non-destructive testing (NDT) which provides useful information for calibrating structural models. The first part of this work describes the behavior of tie-rods, emphasizing the key role played by cross-section stiffness, which is usually neglected in the case of cables. Particular attention is then given to common effective parameters and dynamic aspects in terms of acquiring the set-up and which modal parameters to examine. For new insights into methods for assessing historical tie-rods and evaluating the reliability of analytical and numerical predictions, laboratory tests on four samples with typical cross-sections were carried out on historical metal tie-rods. A set of 224 configurations, including various methods of excitation, boundary conditions, and stress states, were analyzed. In addition to laboratory parameters, this analysis also includes details of sensor positions and number of modes to be examined, and proposes a simplification for less time-consuming tests on-site. [ABSTRACT FROM AUTHOR]

In this study, two different historical structures built in Trabzon have been processed by ambient vibrations and seismic refraction measurements. One of the investigated historical structures is the Atatürk Pavilion built in the nineteenth century, and the other one is Hagia Sophia which was built in the thirteenth century. These two buildings are among the most important historical buildings in Trabzon and are very important for the tourism of the city. In order to determine peak/s frequency and amplitude from the horizontal-to-vertical spectral ratios (HVSRs), we have performed several measurements of ambient vibrations both inside (at different floors) and outside (on the ground) of structures. We have also conducted seismic prospecting to evaluate the vertical 1D and 2D profile of longitudinal and shear seismic waves, Vp and Vs, respectively. To this purpose, we have performed seismic refraction tomography and MASW. Ambient vibrations and seismic measurements were compared with each other. The results show that average predominant frequencies and HVSR amplitudes of inside and outside of Atatürk Pavilion are 4.0 Hz, 7.8 Hz and 2.6, 2.3, respectively. The Vp values vary from 300 to 2070 m/s, and the Vs for maximum effective depth is up to 790 m/s in Atatürk Pavilion. On the other hand, average predominant frequencies and HVSR amplitudes of inside and outside of Hagia Sophia and its tower are 4.7, 4.4 and 2.4 Hz and 1.6, 1.8 and 6.9, respectively. Vp values range from 450 to 2200 m/s, and Vs for maximum effective depth is also up to 1000 m/s in Hagia Sophia. The frequency values (F0 = Vs/4 h) calculated from the velocities up to the maximum effective depth for Atatürk Pavilion are in good agreement with the predominant frequency values determined from ambient vibrations. Atatürk Pavilion and Hagia Sophia soils have been classed according to Eurocode 8 by using VS30 values. The class was defined as "B." Moreover, the bedrock in studied area is basalt. The high Vp and Vs values are also compatible with the lithology. The HVSR curves measured at the Hagia Sophia show the presence of clear peaks when compared to the Atatürk Pavilion. At the same time, there are marked velocity changes in the Vs sections calculated in both areas. As a result, in both areas there are significant impedance contrasts in the subsoil. However, this impedance contrast is more evident in Hagia Sophia. This could be also compatible with a lithological transition. The possible soil-structure interaction was investigated by using all the results and evaluated in terms of resonance risk. It is thought that the probability of resonance risk at Atatürk Pavilion is low according to the ambient vibrations measurements. However, resonance risk should be taken into consideration at Hagia Sophia site since the predominant frequency values are very close to each other. Finally, this site should be investigated in detail and necessary precautions should be taken against the risk of resonance. [ABSTRACT FROM AUTHOR]