Historical Structures Research Articles

Conservation of Defensive Military Structures Built with Rammed Earth

Earth is a complex material with mechanical and physical behaviors that differ from modern building materials. The conservation of rammed-earth (RE) constructions presents specific difficulties that are challenging to overcome. A lack of knowledge about RE due to its abandonment for decades and interventions adopting materials and repair methodologies designed for conventional constructions have led to inadequate interventions. In the case of historic defensive constructions, the doubts and technical difficulties are even greater due to the nature of so-called military RE (with physical and mechanical characteristics which differ significantly from those of civil, more common RE) and, not least, due to the historical and cultural heritage value of these constructions. Some important interventions have been carried out recently, while others are underway or in the planning stage, and there is a constant lack of information and technical data regarding the best ways to intervene. To fill this gap, the state of conservation of defensive RE structures and the results of interventions carried out throughout history in the southwest of the Iberian Peninsula are being assessed. This article sets out a framework for the subject, identifies material and construction techniques and recognises the main causes of RE constructions’ deterioration and decay. With special focus on the most frequent damages detected in historic military defensive structures built with RE, it analyses and discusses the most common techniques that have been used for the repair and conservation of these particular structures.

Comparative Study on Complete Characterisation of Elastic–Ductile Compressive Behaviour of Aged and New Norway Spruce Timber

ABSTRACT Material properties of historical timber structures may change over time due to decay, change of chemical composition of material, biological agents, climatic conditions, etc. Adequate bending performance requires stiffness and strength both in tension and compression, as well as sufficient ductility in compression. While the focus of most research is on the former quantities, the latter one is generally disregarded. This study gives a comparative analysis on complete characterization of compressive behaviour of recent and 60-years-old aged spruce timber (Picea abies). Parallel-to-grain compressive tests on small-sized specimens were conducted to obtain stress – strain diagrams and to determine failure modes. All material properties of stiffness, strength, and ductility were calculated for each specimen. It was concluded that elastic stiffness, elastic limit stress, and compression strength are virtually invariable after sixty years of service while the ductility decreased and the post-peak behaviour became more brittle. It is also found that end-rolling failure mode can yield the same elastic and stiffness properties as the standard kinkband failure. Climatic changes increase the risk of material deterioration prompting for more thorough monitoring and study of historical timber structures.

The walking dead: Identity, variability, and cultural interactions of funerary behaviors between Crete and mainland Greece during the Early Iron Age (11th to 8th BC)

This paper aims to examine funerary contexts of sites in mainland Greece and compare them with sites on the island of Crete in Ancient Mediterranean during the Early Iron Age, in the period of circa the 11th until the 8th centuries BC. From an integrative approach to the analysis and interpretation of material culture from funerary contexts allow us to understand aspects of the space of the dead, aspects of mortuary practices and their role in the configuration of the historical context of the rise and formation of the polis, especially during the 8th century BC. The comparative analyses also provide a better understanding about contact and interactions in the Mediterranean. This requires us to analyze and consider on the different nature of material culture from funerary contexts, such as types of treatment and deposition/disposal/placement of the body of the dead, the construction of funerary architecture, grave goods, and the agency of the space of the dead in the construction of the funerary topography (funerary landscape). Cultural interactions are material expressions resulting from the exchange of ideas, know-how, technique and technology, beliefs, customs, and behaviors, both from objects and from the movement of people. They constitute a prospective field to address mortuary archaeological data as an active part of death and of the social process of dying. Funerary behaviors assign meanings, build memories and identities to biological death. They bring life to the transition of an active person in the “world of the living” into a passive “material thing” in the “world of the dead”. Thus, the dead, become the “walking dead” and “come to life”. Cultural interactions during the Early Iron Age constitute a fundamental element in the configuration of a new historical structure, the polis, which characterizes the Greek world as a unit – not homogeneous but consisting of heterogeneous and idiosyncratic aspects. Mortuary practices integrate this world of simultaneously standardized and peculiar actions and have crucial roles in the hellenic identity and in the identity particularities of its polis in Greek mainland and Crete.

Investigation of meaning and centrality relationship in the statues used in Çankırı urban landscape

Statue is the three-dimensional concrete form created by the designer with materials that he determines depending on his purpose. Statues in urban landscapes are elements of artistic, aesthetic and cultural importance in the life of societies. In this study, answers to the following two questions are sought: (1) Does the meaning of statues in urban landscapes reach the urbanite? (2) Are the location and characteristics of the placement sites of the statues a factor in this semantic awareness? In this context, first of all, general design principles within the scope of urban landscape design were discussed in this study. Then, 8 statues selected from Çankırı city center were photographed and classified according to their types of use (cultural, historical, traditional, aesthetic, and industrial). Then, the physical components of statues in their relations with urban landscapes, such as volume, form, material and placement, and the factors affecting the perception of societies of statues were examined within the scope of Gestalt theory perception theory and design principles. Finally, the relationships of the statues with the urban landscape were evaluated in terms of their centrality relations using the Graph Common software. As a result of the research, it was observed that the statues in Çankırı were generally not complicated, had symbolic qualities and appropriate preferences were made in the selection of statues. In addition, the statues reflect the historical and cultural structure of the city, but there is a need for sculptural works that will further support the city's identity. Although there are some errors in the location and size of the Ox cart Statue, Embrace Stone and Yaren statues, there are no major problems that cannot be corrected. As a result of the study, recommendations were put forward in the light of all these findings.

Ancient Houses in Ben Tre City: A Multifaceted Approach to Preserve Artistic Architectural Heritage and Boost Local Tourism

The ancient houses of Ben Tre city, dating back to the French colonial period, transcend their historical significance to become essential cultural landmarks with global connections. These houses play a pivotal role in safeguarding Ben Tre's artistic and architectural heritage, aligning seamlessly with the vision of a "Green Ben Tre" in contemporary tourism development. Their unique value lies in the harmonious synthesis of material and spiritual elements, fostering cultural exchange and connecting communities worldwide. This article not only presents initial research findings on the preservation and promotion of the rich values encapsulated within Ben Tre's ancient house system but also explores additional crucial technical solutions. Beyond the study of the effectiveness of the Cement-Stabilized Base (CSB) additive in enhancing soil load-bearing capacity, the paper introduces various technical strategies aimed at conserving the artistic architectural heritage. The focus extends to sustainable construction practices, ensuring the longevity of these historical structures. The study emphasizes the urgent need for conservation, acknowledging the imminent threat of demolition faced by some ancient houses in Ben Tre city. It underscores the importance of sustainable tourism development as a key factor in preserving these invaluable cultural assets for future generations.

Exploring the spatial attributes of streets in Lu Xun’s hometown of Shaoxing, China, through image semantic segmentation

Image semantic segmentation, a deep learning algorithm, enables the recognition of pixel collections that form distinct categories, allowing for the identification of vehicles, pedestrians, traffic signs, pavement, and other road features. In urban and architectural design domains, image semantic segmentation and related techniques empower practitioners and researchers to efficiently analyze the distribution of public spaces. This application facilitates a better understanding of how people interact with urban environments, ultimately improving the design of functional and inviting spaces. This paper presents an analysis of images of different streets within the Lu Xun Heritage Area in Shaoxing, Zhejiang Province, China, which were obtained through onsite photography. The images were sampled, segmented, and compared to assess the spatial characteristics of distinct street types. A self-trained semantic segmentation model based on the Cityscapes dataset and the PaddlePaddle framework was employed to statistically analyze space variations across various dimensions. This analysis contributes to a better understanding of historical street structure and provides insights into the integration of artificial intelligence in urban planning and design.

Roman stone masonry walls: The application of Ground Penetrating Radar to ancient structures

An investigation on estimating Roman stone masonry wall thickness using non-invasive Ground Penetrating Radar (GPR) and Light Detection and Ranging (LiDAR) technology is presented in this paper. Historical building conservation and structural evaluation require correct wall thickness measurements. The methodology encapsulates data collection, signal processing, and interpretation techniques, including the use of local frequency attributes tailored for historical masonry structures. The main perimeter wall at the Circus of Maxentius, Rome, Italy, is used as the case study. The results indicate that GPR is capable of accurately estimating the thickness of Roman stone masonry walls. By conducting a comparative analysis against a wall section with a known thickness, it has been demonstrated that GPR is a dependable and precise method for conducting archaeological and architectural research. This study highlights the potential of using GPR attributes as a non-destructive investigative methodology in the field of heritage preservation. Future research includes extracting and improving further attributes and applying this approach to other historical structures.

Sustainable system with non-intrusive anchors for the preservation of historic steel structures

This study introduces an innovative, non-invasive anchorage system for preserving historic steel structures, such as riveted bridges, which are valuable heritage assets requiring maintenance that does not compromise their structural integrity. Overcoming the accessibility and limitations of traditional methods, the proposed system employs clamp-based connections, allowing for removable anchoring without invasive interventions like welding or drilling. We demonstrate the applicability and efficacy of this system through Finite Element Model (FEM) simulations and laboratory experiments, validating its load-bearing capacity necessary for maintenance and inspection. Installing these elements on riveted steel bridges highlights the practical application of the developed technology, underscoring its potential for the sustainable maintenance of historic steel structures without compromising their integrity or historical value.

Termite IPM in historic sites

Abstract Given the traditional use of wood, historical structures are susceptible to termite damage which can irreversibly affect their historical significance. Methods like drilling into the foundation for termiticide injection are impractical and potentially harmful to the structural integrity of these structures. Moreover, the location of these structures in ecologically sensitive areas prohibits the use of soil termiticides due to potential contamination of groundwater, rivers, or oceans. Termite Integrated Pest Management (IPM) strategies include baiting programs that use minimal quantities of benign insecticides to reduce environmental impact. This approach is consistent with the risk management component of termite IPM. Bait systems are proven to be effective in eliminating termite colonies, contributing to the benefit component of IPM by preserving the value of historical sites. This article discusses successful baiting interventions at notable locations such as the Statue of Liberty National Monument, New York, USA, the Christiansted National Historic Site in St. Croix, US Virgin Islands, and the Historic Tzu-Su Temple in Taiwan.

Recent methods of visualization used in the diagnosis and consolidation of historic structures

The subject addresses heritage objects that are subject to degradation processes caused by both natural and anthropogenic factors. One of the current solutions is directed towards a varied range of scientific instruments, thus facilitating the analysis and diagnosis of the concerned buildings, contributing also to the identification of materials and techniques used and providing information about any previous interventions of conservation attempts. Recent visualization methods used in the diagnosis and consolidation of historic structures can utilize both three-dimensional laser scanning technology and laser interferometry as a diagnostic method, as well as alternative methods such electrometry, magnetometry and ground penetrating radar devices. The subject aims to address how heritage objects can be secured using 3D scanning technologies. The case studies were conducted on the Bezdin Monastery Complex, the ”Saint Martyr Gheorghe” Church, the ”Saint Martyr Filimon” Monastery and the former Metropolitan Summer Residence in Sibiu. The selected case studies illustrate the methodology for obtaining and processing field data, as well as the use of this data in the diagnosis process and in selecting appropriate consolidation options for these historical structures based on obtained results. These technologies have provided specialists with the possibility of extracting vital information both in the diagnostic phase and throughout the implementation of restoration works. Advanced scanning technologies of today have enabled the creation of a database with the capability of providing pertinent information about a building’s past, starting from its initial stage, up to the completion of execution works, which significantly aids in facilitating the process of diagnostic analysis and structural calculation.

Shaping a Modern Townscape in The City Centre Area: The Case of Vilnius

Abstract The development of a contemporary townscape within the historical urban structures is a phenomenon of this period that has been going on in Lithuania for about 20 years. This is an ongoing process with an uncertain outcome, as the rapidly changing urban design trends require quick responses to current needs. It is necessary to modify, revise, and supplement the concepts and existing legislation accordingly. This article examines the factors leading to the emergence and formation of the modern townscape in Vilnius, as well as the documents governing the city’s development after gaining independence. It presents an evaluation of the newly established urban structures in the central part of Vilnius and identifies the challenges and problems in shaping the contemporary townscape. The results of the study allow us to identify what actions must be taken in order to form a high-quality modern townscape, starting with self-evaluation of what has been done and ending with the creation of a dynamic urban model that would respond to constantly changing needs.

Structural safety of existing masonry-tunnel-linings: a methodology derived from existing buildings approaches

Masonry linings were the primary solution for tunnels before the introduction of reinforced concrete. As a result, many tunnels with masonry linings have been in operation for over a century and may exhibit damage due to ageing and prolonged water infiltration. Currently, there are no specific regulations for the static verification of masonry tunnels. These tunnels share characteristics and problems with historic masonry structures such as bridges and building facades. Therefore, the scientific literature and normative references developed for masonry heritage structures were here considered. This work focuses on estimating the masonry strength of tunnel linings. To demonstrate the proposed methodology and the addressed problems, the ‘Giovi’ tunnel on the historic Genoa-Valle del Po motorway in Genoa, Italy was selected as an exemplary case. The masonry’s resistance is measured in situ using flat-jacks and estimated using methodologies proposed for both new and existing buildings. The comparison of these methodologies highlights the unique characteristics of tunnel linings, including thick mortar bed-joints and massive curved masonry walls, with only one free face.

Diaphragm effect of unreinforced historical masonry vaults

In historical masonry structures, and particularly in churches, vaults have a fundamental role in bearing the vertical loads of floors and roofs. However, in past earthquakes they have proved vulnerable, representing a source of fragility under horizontal loading. In addition, the global seismic behavior of masonry structures is strongly affected by the stiffness of flooring elements (diaphragm effect), which, when sufficient, allows for transfer of horizontal actions to stiffer wall working in-plane.In this paper, the diaphragm effect of historical masonry vaults under horizontal loads is investigated numerically. A parametric nonlinear Finite Element model of a cross vault is subjected to in-plane shear actions on two supports to evaluate the response and damage during an earthquake. This work is preparatory for future physical testing activities on scaled prototypes to be performed within a broader research project, aimed at the enhancement and exploitation of artistic and cultural heritage.

Diagnosis of Historic Reinforced Concrete Buildings: A Literature Review of Non-Destructive Testing (NDT) Techniques

Non-destructive testing (NDT) techniques are employed by many authors as reliable and effective methodologies to investigate the current conservation state of historic buildings and to follow up its evolution in response to the surrounding environmental changes. This paper briefly reviews the scientific articles dealing with NDT techniques applied to historic reinforced concrete (RC) buildings. To this purpose, 32 articles were selected through the steps of the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) flow diagram and critically analysed. It emerges that Acoustic Emission and Ultrasonic techniques, Thermography, Rebound Hammer, and Electromagnetic techniques (e.g., Eddy Current and Ground Penetrating radar) are commonly employed due to their ability to detect damage in RC structures. As a result, the combined use of acoustic and mechanical methods (also known as “SonReb” Rebound Hammer and Ultrasonic Pulse Velocity) is found to be the approach more frequently used in the revised documents. This work allows to guide in the selection of NDT techniques to study the rate of decay, if any, and shows the way towards the development of new early warning approaches for historic RC structures.

Effectiveness of the Beti Bachao Beti Padhao Campaign: Application of Nudge Theory to Address Gender Imbalance in Northern India

Gender imbalance is a significant socio-cultural issue. The Beti Bachao Beti Padhao (B3P) campaign of the Indian Government referred to nudge theory to promote gender equality and reduce the perceived burden of the girl child. It has however shown limited effectiveness in certain northern states like Haryana where it is being run in 95% of the districts. This research investigates how nudge theory can be better employed to bring about the required behavioral change. The B3P campaign includes financial incentives, facilitation of female education, and public awareness initiatives. Regardless of these efforts, the preference for a male child continues to dominate in states like Haryana, and Punjab, and even urban territories like the national capital- Delhi reversing the early success of the initial few years. Literature indicates that this inclination towards the male child is rooted in a multilateral complex web of historical and socio-economic structures that ensure that sons are viewed as economic assets. A pan- India review reveals significant regional differences and seemingly highlights that the preference for a male child is influenced by inheritance rights and familial considerations, perpetuating the benefits associated with sons.

Enhancing heritage building preservation with MCDM and HBIM: A research proposal

Conservation and management of architectural heritage is gaining importance in the context of responsible development and environmental awareness. The integration of Heritage Building Information Management (HBIM) and Multi-Criteria Decision-Making (MCDM) is capable of addressing the challenges of heritage preservation decision-making. HBIM, tailored to historic structures, serves as a digital repository of geometric and semantic data of any kind related to these buildings, while MCDM provides a structured framework for decision-making, considering technical and subjective aspects.This research proposal aims to optimize heritage preservation decision-making processes by identifying possible decisions, designing user-oriented workflows, and integrating them into a cohesive framework. This approach seeks to foster collaboration, provide practical guidelines, and contribute to effective informed decision-making by all stakeholders involved in heritage management. Despite limitations, the research proposal has the potential to improve the effective integration of decision-making processes in the management of heritage structures.

Mechanical characterization of Glass Fibre-Reinforced Air Lime-Based Mortars

The basic issue in determining the deformational properties of masonry is to conduct a comprehensive experimental characterization of the masonry components' materials, including their mechanical properties. This characterization process is even more important for new sustainable mortar solutions, especially in the context of strengthening and renovating existing masonry buildings, including historic structures. The work presents and discusses the mechanical tests carried out on a mixed cement-lime mortar based on air lime and reinforced with the addition of industrial glass fibres. Mechanical testing on prisms (40 × 40 × 160 mm) and cylinders (60 diameter × 120 mm height) demonstrated the beneficial impact of fibres in the mortar mixture analysed specifically in terms of improved compressive, flexural and splitting post-peak behaviour.

Principles and technologies of historical structures consolidation, case study of Banloc castle complex

Historical monuments (palaces, churches, protected urban areas, so on) are integral part of the national cultural heritage which need activities and measures to protect them. The Banloc complex, located in the west of Romania, encompasses five buildings: the castle, the hunting pavilion, the kitchen, housekeeper house, and the stall. This study involves historical, architectural, structural and physical-chemical investigations with the aim of finding the correct restoration solutions, in good agreement with the Venice Charter, respectively the Nara Charter. Being affected by time and by the seismic sequence (Mw 5.6), the restoration of the building is absolutely necessary for recovering the functionality, structural solution and highlighting the artistic elements. Some analytical techniques, as: X-ray diffraction (XRD), Wavelength Dispersive X-ray fluorescence (WDXRF), optical microscopy (OM), and zoom microscopy, Infrared spectroscopy Fourier Transformed (FTIR), and Raman spectroscopy, have been used in this paper in order to clarify the main aspects about the structure, composition and morphological of the samples collected from Pavilion building. The oxides composition, and the possible organic impurities has been identified by WDXRF amd FTIR/Raman spectra, respectively. The microscopy images revealed the colours, fissures, cracks and even holes due to the time weathering processes, and damages they suffered in time.

Some dimensional-geometric modulations of the Stonehenge megalithic complex

The article is devoted to the modulated dimensional-geometric peculiarities of the Stonehenge megalith and continues the theme of our previous publications devoted to such megalithic objects as the “stone ship” Ales Stenar, small circle in Nabta Playa, and the outer “circle of stones” in Clava. By “modulation” we mean the use of a large module in the size of historical structures, quantitatively equal to the simple number of known historical linear measures (the simple number 37 is most often identified). A more detailed justification of the method is given in “Hypothesis of the dimensional-geometric scheme of the Nabta-Playa megalith landscape monument” including connections with the dimensional-geometric features of ancient Egyptian architecture are also shown there.

The effect of sand on the mechanical characteristics of gypsum-lime mortars for heritage buildings

The endurance and preservation of historical buildings greatly depend on the integration of lime into the mortar used for masonry linings. Therefore, conducting mechanical assessments of existing and restoration mortars is crucial to ensure their compatibility and prevent potential issues. This article emphasizes the role of sand in enhancing the efficiency and resilience of gypsum-lime mortars by examining how it influences on their mechanical properties. The main aim of this research is to provide practical guidance for the sustainable restoration and conservation of historical edifices. The study examines the mechanical attributes of gypsum-lime mortars for restoring historical structures, with a specific focus on evaluating the impact of different sand proportions (10%, 15%, and 20% by gypsum volume). Moreover, the results were scrutinized to comprehend the compositions, structural features, and compressive strength. Among the six mortar blends, the addition of 15% sand was identified as the most effective augmentation to gypsum-lime, demonstrating comparable workability. Furthermore, this proportion exhibited improved compressive and flexural strengths on the seventh day compared to pure gypsum-lime. This highlights the potential economic application and further enhancement of this locally sourced product in various finishing applications. Notably, gypsum-lime mortar infused with 15% sand exhibited optimal structural properties, particularly in terms of compressive strength.