Conservation Of Built Heritage Research Articles

Editorial for the Special Issue “The Future of Built Heritage Conservation”

Editorial for the Special Issue “The Future of Built Heritage Conservation”

Are Nature-based Solutions for Built Heritage Conservation Resilient to Climate Change? The Response of Grass-based Soft Caps in Britain and Ireland to Future Climate Scenarios

ABSTRACT Nature-based solutions (NbS) offer an exciting opportunity to work with nature to conserve heritage sites and objects. Soft capping is a novel form of NbS used commonly in Britain and Ireland to help conserve ruined and free-standing walls; soil and vegetation is placed on the wall head to help reduce deterioration by buffering thermal fluctuations and regulating moisture. While this conservation practice has proved cheaper and more effective at reducing deterioration than traditional hard capping, soft caps need to be resilient to future environmental changes. Previous research has shown that the sedum species commonly used in soft caps are vulnerable to climate change. Thus, following feedback from an interactive webinar with practicing heritage professionals, here we assess the climate resilience of four grass species commonly found in western Europe as possible soft-capping species: Festuca rubra (red fescue), Poa pratensis (smooth meadow-grass), Catapodium rigidum (fern-grass) and Poa annua (annual meadow-grass). We use species distribution modelling (Maxent) to assess the likelihood of species survival by mid and end century based on presence probabilities derived using three climate models (HadGEM3-GC31-LL, IPSL-CM6A-LR, and MIROC6). Results show that all four species are resilient under mid-century projections, and P. annua proved resilient under all scenarios. Therefore, using turf-based soft caps incorporating one or more of these grass species could enhance the future resilience of this conservation technique. Given the growing interest in the use of nature-based approaches to heritage conservation, our study represents an important attempt to account for and adapt to a changing climate.

Historic Built Environment Assessment and Management by Deep Learning Techniques: A Scoping Review

Recent advancements in digital technologies and automated analysis techniques applied to Historic Built Environment (HBE) demonstrate significant advantages in efficiently collecting and interpreting data for building conservation activities. Integrating digital image processing through Artificial Intelligence approaches further streamlines data analysis for diagnostic assessments. In this context, this paper presents a scoping review based on Scopus and Web of Science databases, following the PRISMA protocol, focusing on applying Deep Learning (DL) architectures for image-based classification of decay phenomena in the HBE, aiming to explore potential implementations in decision support system. From the literature screening process, 29 selected articles were analyzed according to methods for identifying buildings’ surface deterioration, cracks, and post-disaster damage at a district scale, with a particular focus on the innovative DL architectures developed, the accuracy of results obtained, and the classification methods adopted to understand limitations and strengths. The results highlight current research trends and the potential of DL approaches for diagnostic purposes in the built heritage conservation field, evaluating methods and tools for data acquisition and real-time monitoring, and emphasizing the advantages of implementing the adopted techniques in interoperable environments for information sharing among stakeholders. Future challenges involve implementing DL models in mobile apps, using sensors and IoT systems for on-site defect detection and long-term monitoring, integrating multimodal data from non-destructive inspection techniques, and establishing direct connections between data, intervention strategies, timing, and costs, thereby improving heritage diagnosis and management practices.

A Comprehensive Heritage BIM Methodology for Digital Modelling and Conservation of Built Heritage: Application to Ghiqa Historical Market, Saudi Arabia

A Comprehensive Heritage BIM Methodology for Digital Modelling and Conservation of Built Heritage: Application to Ghiqa Historical Market, Saudi Arabia

Economic and Institutional Factors Influencing the Selection of Project Delivery Models for Built Heritage Conservation in India

ABSTRACT Selecting a suitable project delivery method is one of the most critical decisions responsible for project success in heritage conservation. This is an area where projects have greater uncertainties and governance issues in comparison to other building projects. India has a huge inventory of built heritage sites, but the heritage conservation sector is highly fragmented, with a wide range of project delivery methods. This paper discusses the selection of project delivery in the Indian context, using the theoretical lenses of agency theory, transaction cost economics (TCE), and institution theory. A conceptual framework has been proposed to explain the selection based on economical and institutional constructs. Our conclusion is that when institutional factors are weak, projects are executed departmentally or through non-priced contracts. In contrast, strong institutional forces discourage non-priced contracts and replace them with priced contracts.

HBIM for Conservation of Built Heritage

Building information modeling (BIM) has recently become more popular in historical buildings as a method to rebuild their geometry and collect relevant information. Heritage BIM (HBIM), which combines high-level data about surface conditions, is a valuable tool for conservation decision-making. However, implementing BIM in heritage has its challenges because BIM libraries are designed for new constructions and are incapable of accommodating the morphological irregularities found in historical structures. This article discusses an architecture survey workflow that uses TLS, imagery, and deep learning algorithms to optimize HBIM for the conservation of the Nabatean built heritage. In addition to creating new resourceful Nabatean libraries with high details, the proposed approach enhanced HBIM by including two data outputs. The first dataset contained the TLS 3D dense mesh model, which was enhanced with high-quality textures extracted from independent imagery captured at the optimal time and location for accurate depictions of surface features. These images were also used to create true orthophotos using accurate and reliable 2.5D DSM derived from TLS, which eliminated all image distortion. The true orthophoto was then used in HBIM texturing to create a realistic decay map and combined with a deep learning algorithm to automatically detect and draw the outline of surface features and cracks in the BIM model, along with their statistical parameters. The use of deep learning on a structured 2D true orthophoto produced segmentation results in the metric units required for damage quantifications and helped overcome the limitations of using deep learning for 2D non-metric imagery, which typically uses pixels to measure crack widths and areas. The results show that the scanner and imagery integration allows for the efficient collection of data for informative HBIM models and provide stakeholders with an efficient tool for investigating and analyzing buildings to ensure proper conservation.

Digital Tools for the Preventive Conservation of Built Heritage: The Church of Santa Ana in Seville

Historic Building Information Modelling (HBIM) plays a pivotal role in heritage conservation endeavours, offering a robust framework for digitally documenting existing structures and supporting conservation practices. However, HBIM’s efficacy hinges upon the implementation of case-specific approaches to address the requirements and resources of each individual asset and context. This paper defines a flexible and generalisable workflow that encompasses various aspects (i.e., documentation, surveying, vulnerability assessment) to support risk-informed decision making in heritage management tailored to the peculiar conservation needs of the structure. This methodology includes an initial investigation covering historical data collection, metric and condition surveys and non-destructive testing. The second stage includes Finite Element Method (FEM) modelling and structural analysis. All data generated and processed are managed in a multi-purpose HBIM model. The methodology is tested on a relevant case study, namely, the church of Santa Ana in Seville, chosen for its historical significance, intricacy and susceptibility to seismic action. The defined level of detail of the HBIM model is sufficient to inform the structural analysis, being balanced by a more accurate representation of the alterations, through linked orthophotos and a comprehensive list of alphanumerical parameters. This ensures an adequate level of information, optimising the trade-off between model complexity, investigation time requirements, computational burden and reliability in the decision-making process. Field testing and FEM analysis provide valuable insight into the main sources of vulnerability in the building, including the connection between the tower and nave and the slenderness of the columns.

Machine Learning-Based Monitoring for Planning Climate-Resilient Conservation of Built Heritage

Machine Learning-Based Monitoring for Planning Climate-Resilient Conservation of Built Heritage

ANALYSIS OF THE SPATIAL-SEMANTIC COHERENCE IN THE GETTY AAT VOCABULARY DATA STRUCTURE - AN EDUCATIONAL EXPERIENCE

Abstract. The paper explores the integration of Geomatics and architectural surveying into the educational context of Geomatic for Built Heritage Conservation course within the Master on Architectural Design, in which a multidisciplinary teaching approach is applied, emphasizing the importance of holistic knowledge encompassing historical, geometric, material, and structural aspects for the conservation and restoration of architectural heritage.A central theme is the role of Geomatics and 3D modelling in historical built heritage documentation, assuming the creation of three-dimensional models as a foundation for integrating various thematic data, enabling interdisciplinary studies, and facilitating knowledge representation and communication.The paper delves into the challenges and strategies of semantic 3D modelling. It discusses the necessity for a flexible and layered informational model, integrating spatial, geometric, and semantic data. The complexity of semantic annotation is explored, considering the subjectivity and cultural context inherent in identifying and describing architectural elements. The educational approach employed in fostering critical thinking among students, particularly in interpreting cultural heritage issues related to documentation and recording, is presented.A case study involving Pitti Palace in Florence is considered. An attempt to implement the Getty Vocabulary on Art & Architecture Thesaurus for semantic annotation is described, emphasizing the need for a coherent alignment between the 3D model and controlled vocabulary hierarchy. The study concludes with insights from the student's experience, highlighting the difficulties in aligning spatial and semantic elements within existing controlled vocabularies and suggesting avenues for future developments in refining these vocabularies for enhanced spatial-semantic coherence in 3D modelling applications.

Stochastic-based vulnerability curves for the out-of-plane seismic safety assessment of URM walls

Earthquakes are a major cause of damage and human losses to the built environment, including cultural heritages, monumental buildings and historical centers. In the last decades, the seismic performance of buildings has received special attention due to the interest in the built heritage conservation and protection of human life, particularly with respect to masonry structures which have shown evidence of poor behavior once subjected to seismic loads. The present work contributes to the seismic safety assessment of the out-of-plane behavior of unreinforced masonry walls through a displacement-based approach, providing the capacity for different out-of-plane geometric indexes and its seismic response in different earthquake-prone regions. The analyses are conducted using a seismic probabilistic framework, considering the most common out-of-plane mechanisms, different material properties, various slenderness ratios, and a wide range of seismicity levels to cover the seismic hazard in Europe. The results presented can be useful for seismic safety assessment and to incorporate vulnerability models for seismic risk analysis.

The concept of risk and its measurement in the field of built heritage conservation: critical aspects and potential improvements

The term risk has been defined in different ways in various scientific areas. As a result, there is a certain confusion over the meaning and the use of the term. In order to understand better the variety of approaches to the concept of risk and consequently its measurement, representative studies, carried out by re- searchers and professionals, are considered. Which are the most important as- pects that built heritage conservation adopted and developed and how these as- pects have led to the use of different methods of assessment and evaluation of risks? Secondly, different methods of risk assessment and evaluation, adopted in various activities of the built heritage conservation process, are selected and an- alyzed. With the aim to highlight their strengths and limitations, a comparison is drawn, permitting us to have an overall picture of the available methods and at the same time to identify the eventual gaps and the critical aspects of the re- search/practice. Lastly, based on the acknowledgment of the limits and the prob- lems of the various methods, suggestions for improvement are made.

Capacity Building Strategies for Built Heritage Conservation of George Town World Heritage Site, Penang

ABSTRACT George Town’s inscription as a world heritage site on July 7 2008 has profound ramifications for the city’s subsequent functionalities, image, and identity. Since the UNESCO inscription, heritage shophouses in George Town World Heritage Site (GTWHS) were purchased en-bloc by investors and massive conservation of shop houses took off. Among the key issues faced by GTWHS is a shortage of the right quantity and quality of human capital in building conservation which, in turn, will threaten the authenticity and integrity of the city’s built heritage, if conservation is done without applying conservation principles and proper skills. While there are strategies in George Town’s Special Area Plan to manage the heritage site, there is a dearth of strategies related to capacity building in the city’s heritage sector. Against this backdrop, the paper aims to propound the relevant strategies to enhance George Town’s capacity building for building conservation works. Based on qualitative techniques, this study interviewed heritage experts to identify suitable strategies in capacity building for GTWHS. This paper recommends that existing strategies should garner collective participation from all stakeholders. The strategies proposed should be implemented as soon as possible to ensure quality and continuous generation of the right skills and knowledge toward sustainable capacity building for George Town’s built heritage.

Quantitative Estimation of the Internal Spatio–Temporal Characteristics of Ancient Temple Heritage Space with Space Syntax Models: A Case Study of Daming Temple

Ancient temple heritage space is a subcategory of integrated spaces with profound religious architecture, culture, and landscape. The temporal and spatial characteristics, spatial layouts, and functionalities of ancient temples are gradually transformed during different periods in their development. However, quantitative topological estimation tools, e.g., space syntax and detailed digital spatial models, have seldom been adopted in related studies on ancient temples. Daming Temple is a typical representative of the revitalization of Buddhism monastic building heritage in China. This research studies the spaces of Daming Temple, Yangzhou City, in three different periods and explores its spatio–temporal characteristics based on two space syntax models, i.e., the angle segment analysis (ASA) model and the visibility map analysis (VGA) model. By multi-step quantitative estimation, changes in the mean depth (MD), mean connectivity, and intelligibility of the temple have been observed. The global spatial structure is thoroughly revealed, which indicates the changes in the ‘temple-residence-garden’ inter-relationship. It is indicated that dynamic spatio–temporal characteristics of the temple have been undergoing changes chronically. Some phenomena are found to be effective in offering reasonable explanations for these changes, i.e., the changes in relationships among spaces, visitors’ pathfinding difficulties, and spatial design techniques. It also found that there are certain correlations between temporal–spatial changes and spatial conservation strategies for building heritages. The case study can provide some valuable references for the conservation, reactivation, and redesign of related historical and cultural building heritage in East Asia.

The Boom in Nanomaterials for Built Heritage Conservation: Why Does Size Matter?

There is no doubt that nanotechnology and nanoscience open new doors to new applications and products that can potentially revolutionize the practice field and how we conserve built heritage materials. However, we are living at the beginning of this era and the potential benefits of nanotechnology to specific conservation practice needs are not always fully understood. This opinion/review paper aims to present reflections and answer a question that we are often asked when working directly with stone field conservators: why should we use a nanomaterial instead of a conventional product? Why does size matter? To answer this question, we revise the basic concepts of nanoscience with implications for the built heritage conservation field.

Characterization and Assessment of Performance of Innovative Lime Mortars for Conservation of Building Heritage: Paimogo’s Fort, a Case Study

Along the Portuguese coastline, several military fortifications were built with the intention to protect the territory from the constant military threat from the sea. These constructions have been subjected, during centuries, to a very aggressive environment; the renders, whose main function is the protection of walls, are particularly exposed to such actions. Nossa Senhora dos Anjos de Paimogo’s Fort, better known as the Paimogo’s Fort, is one of these fortifications, built in 1674 and classified of public interest since 1957. Within the scope of the “Coast Memory Fort” Project of EEA Grants Culture Programme 2014–2021, promoted by the Municipality of Lourinhã, repair mortars are being developed for the preservation of the Fort, considering the physical–mechanical and chemical characteristics of the pre-existing mortars and of the substrate, as well as the aggressive environmental conditions. In this work, several mortar compositions, compatible with the original mortars and designed to resist the aggressive environment, are briefly described and their main physical and mechanical characteristics are analysed and compared in successive ages. Different binder mixes were used, and a fine-tuning of the aggregate was carried out. Assessment of sequential wetting/drying cycles’ effect on the mortar’s behaviour is also presented. The laboratory results reveal that mortars with additions of 30% of quicklime present the best behaviour (with the lowest water absorption and highest strength). Moreover, the substitution of part of the siliceous sand by limestone aggregate, in general, increases the mortars’ mechanical strength; however, the drying occurs slower, which could compromise the durability of these mortars if a good balance is not achieved.

Advances in Nanolime and Other Nanomaterials for Built Heritage Conservation

This Special Issue examines the synthesis, characterization, and manufacturing of nanoparticles and their potential advantages and applications for the conservation of built cultural heritage materials [...].

New Materials and Technologies for Durability and Conservation of Building Heritage.

The increase in concrete structures' durability is a milestone to improve the sustainability of buildings and infrastructures. In order to ensure a prolonged service life, it is necessary to detect the deterioration of materials by means of monitoring systems aimed at evaluating not only the penetration of aggressive substances into concrete but also the corrosion of carbon-steel reinforcement. Therefore, proper data collection makes it possible to plan suitable restoration works which can be carried out with traditional or innovative techniques and materials. This work focuses on building heritage and it highlights the most recent findings for the conservation and restoration of reinforced concrete structures and masonry buildings.

Post-Conservation Evaluation (PCE) Framework for Built Heritage Conservation within UNESCO World Heritage Sites: Adaptive Reuse Museums in George Town, Malaysia

Post-Conservation Evaluation (PCE) Framework for Built Heritage Conservation within UNESCO World Heritage Sites: Adaptive Reuse Museums in George Town, Malaysia

Characterization of Traditional Coatings in Earthen Vernacular Architecture in the Limarí Valley: Their Role in the Conservation of Built Heritage in Chile

Despite its seismic activity, Chile has a large number of heritage buildings built with earth. Their conservation depends on elements such as roofing and foundations, but also on the quality of renders and finishing materials. This study seeks to identify and characterize the coating systems and materials used on the wall surfaces of earthen heritage structures in the Limarí valley, Chile, seeking to contribute to the dissemination, promotion, and preservation of these traditional renders. The case studies included are historic buildings in various Limarí valley villages. Render and plaster samples of earthen built heritage were taken for analysis from a diversity of wall structures (such as adobe, pandereta, or quincha) and finishing techniques. Despite differences, the conclusions of our fieldwork and sample observations and analysis allow us to identify effective, common coating systems and finishes.

Incompatible: Modern Built Heritage Conservation versus Value-Based Addition Design at Canada’s Capital Historic Sites

ABSTRACT Heritage conservation’s modernist underpinnings limit engagement with heritage value, resulting in incompatible additions to historic places. A good example is the controversy surrounding the proposed addition to the Château Laurier National Historic Site in Ottawa, Canada, designed by Peter Clewes and approved by the City of Ottawa in February 2021. The addition’s defenders used the Standards and Guidelines for the Conservation of Historic Places in Canada’s modern dictums, particularly legibility and the supremacy of expert knowledge, to justify the Neo-Modernist addition against public outcry. This paper defends the public’s cries for a more fanciful, historicist addition. It argues that additions to historic places should be more than visually and physically compatible. Additions to heritage sites should be stylistically and intellectually compatible and engaged in dialogue with a site’s heritage values. It asks, what do new additions communicate about the original historic site? How do they help or hinder our understanding of the site’s social or historical significance? Designers and evaluators of new additions should ask themselves these questions. They should more closely consider the impact of new additions on historic places’ heritage values. Such consideration may reduce friction between practitioners and the wider public.