Earthen Architectural Heritage Research Articles

Earthen Architectural Heritage in the Gourara Region of Algeria: Building Typology, Materials, and Techniques

Earthen Architectural Heritage in the Gourara Region of Algeria: Building Typology, Materials, and Techniques

Above the Ravines: Flood Vulnerability Assessment of Earthen Architectural Heritage in Quito (Ecuador)

Floods represent one of the most threatening risks for earthen architectural heritage. Developing risk assessment tools is considered crucial to mitigate the risk and to protect heritage buildings. Due to its hygroscopic nature, earthen architecture is generally considered to be vulnerable to water, requiring a specific analysis. This paper proposes a vulnerability assessment method for earthen buildings in flood-prone areas. Based on the evaluation of the susceptibility of the building’s components and characteristics, the method allows for quantifying the vulnerability of the assets, in non-monetary terms. An application of the methodology is carried out assessing a selection of earthen construction in Quito Historic Centre (Ecuador). The results show the influence of each component in the global vulnerability of the earthen buildings. The response of different construction techniques and the importance of the maintenance of heritage buildings is exposed. Vulnerability assessment methods at the meso-small scale constitute the foundation for risk assessment. Thus, this study aims to provide a significant assessment tool that can be used for further analysis and future lines of research, aiming to protect cultural heritage that is at risk.

Analysis of the earthen architectural heritage in Piedmont (northern Italy): typologies, construction techniques and materials

Piedmont is characterized by the presence of numerous earthen buildings mainly concentrated in the province of Alessandria. Studies conducted over the last decade, however, have shown the presence of interesting examples of these buildings also in the provinces of Asti, Torino, Biella and Cuneo. They are generally two-storied rural constructions, built with both fired bricks (for the bearing structures) and adobe (for internal and external walls).

Experimentation of Earth-Gypsum Plasters for the Conservation of Earthen Constructions

ABSTRACTWidely spread in many countries, earthen architectures bear important and significant witness to knowledge, building techniques, and technological culture. The preservation of the earthen architectural heritage, as well as the use of this material in contemporary architecture, asks for the experimentation and the development of proper materials and intervention techniques in order to moderate and prevent any process of weathering which may compromise the conservation of the whole earthen heritage over time. The research aim of this article is to design and test earth-based plasters prepared mixing earth and gypsum, with the addition of natural or synthetic products, which can offer an effective means of protection against the atmospheric agents characterising the places in which the constructions are or will be built.

Technical Strategies for Conservation of Earthen Archaeological Architecture

The preservation of earthen architectural heritage is extremely complex due to the diversity of its constituent materials and potentially rapid physical deterioration. Interventions on historic earthen architecture throughout the world have shown very distinct levels of success, but there is no single procedure or combination of conservation procedures that guarantee success. One of the problems is the lack of knowledge about the behaviour of soil as the material component, and its relationships both with other materials, and associated natural and cultural environments. This article analyses some technical considerations that have influenced the preservation of earthen archaeological remains, through critical analysis of the existing bibliographic references from the proceedings of specialized international conferences that have taken place in the last twenty years.

Deterioration mechanisms of building materials of Jiaohe ruins in China

Almost all defects of earthen buildings such as roughening, erosion, volume reduction, cracking as well as crazing, etc., have been witnessed in the ancient city of Jiaohe, an earthen architectural heritage in northwest China. In this paper, their long-term durability and deterioration due to prolonged exposure to environmental factors were studied, based on the basis of field investigation and laboratory analysis. The results indicated that the deterioration of building materials should be attributed to their basic properties, including density, particle size distribution, soluble salts, mineral, mechanical strength, etc., and interaction with environmental factors. And then, four main deterioration modes can be identified, namely: wind-related deterioration, water-related deterioration, temperature-related deterioration and chemical related deterioration. It can be concluded that the greatest deterioration was wind-related deterioration on west-north facing façades, and chemical related deterioration on the surface of building materials.

The earthen architectural heritage. Historiographical contributions and the appreciation of its values in the context of the Spanish popular architecture

The earthen architectural heritage and, in general, the built ensembles integrating the so called “vernacular architecture”, have been repeatedly investigated for more than a century by archaeologists, architects, ethnologists, historians or geographers. During the last thirty years we can find a significant progress in the procedures for studying, cataloguing, protecting and watching over these cultural goods, which are representative of the diverse ways of inhabiting and constructing in the different regions of the world. However, currently there are few interventions in this kind of heritage that one can consider truly scientific, which is even more obvious in the case of the earthen buildings. In fact, the earth-built architectural heritage is one of the most fragile and endangered sections in the vernacular heritage, regardless of what we find barely developed up to now the essential intervention criteria. To go in depth regarding the essential features of this kind of architecture, identify its main values as cultural landscape shaper and emphasize the most important historiographical contributions on the subject are the main goals of this paper.

The Intervention of Earthen Heritage in Seismic Areas and the Conservation Charters

Earthquakes are recurring natural phenomena that cause cumulative damage to earth constructions that can lead to their collapse. The discovery of earthen architectural heritage in Peru, has led to the re-exposure of adobe buildings, increasing their vulnerability to seismic activity. How can we prevent protect them from further damage their loss and Due to their gradual and progressive destruction, earth constructions located in seismic areas constitute a critical and unique case. The structural response of stone masonry joined with mud mortar depends on the weakest of their construction materials: earth. This paper presents the criteria for structural conservation of earthen architectural heritage and tools for seismic-resistant reinforcement developed by field experts during the last 25 years. The concepts of reinforced earth and liquid mud injection, developed by the Pontifical Catholic University of Peru (PUCP) with support from the Getty Conservation Institute (GCI), are also included in this work. The article also analyzes recent cases of the re-intervention of earth monuments initially restored during the last century and re-destroyed by more recent earthquakes; offers solutions to this situation, ranging from the safest and friendliest to the most aggressive ones. Finally, I concludes expressing the urgent need to reassess the conservation criteria accepted by the International Charters ratified by ICOMOS and UNESCO regarding earthen architectural heritage located in seismic areas.

Recommendations for the Conservation of Earthen Architectural Heritage in Chile

Developing earthen architecture conservation in Chile is a widespread challenge present in different organizations in our country, although a clear legislation has not been defined in order to preserve this important legacy. An extended look throughout the country allows us to understand the state of the art of restoration in Chile. In this respect, the recommendations in this paper are strategic to earthen architecture conservation in the Altiplano and in the Central Valley in the sense that they promote ideas for discussion of a national legislation on conservation and restoration. We believe that understanding how earthen architecture in Chile has been preserved until now enables stakeholders to make better decisions in the long-term; we have focussed this paper on the generation of an emergency strategy that can make it possible for our scarce remaining heritage to resist the next earthquake.

The Conservation of Earthen Architectural Heritage in Seismic Areas

The acceleration of climate change and the increasing frequency of natural disasters mean that there is an urgent need to adapt conservation strategies for architectural heritage to the world’s new demands and situations. This is particularly relevant for the most vulnerable constructions, such as earthen structures. Because of the dramatic effect that earthquakes can have on architecture, and especially on historical monuments, they have been studied for the past 50 years. Earthquakes divide the world in two very distinct geographic areas: seismic and non-seismic. The seismic vulnerability of earthen architectural heritage, such as earthen structures and mud mortar masonry, evidences in by how weak they are when compared to structures built using other construction materials (10 to 15 times weaker). Humanity’s past experience in the conservation of architectural heritage allows us to be aware of the need to improve and eventually perfect the existing conservation charters, which were discussed and signed in Europe in the last century. These charters do not make a distinction between heritage conservation in seismic and non-seismic areas. It is imperative to address this particular issue, as seismic forces can be too strong for earthen constructions to resist, which can lead to their irreparable collapse. Inspired by the Venice Charter and China´s principles as well as by more modern documents, such as the Burra, Mexico, Zimbabwe, Lausana Charters, researchers have tried to establish adequate and resistant conservation guidelines, based on achieving the best structural performance using a minimum permanent and reversible reinforcement. Although this involves causing some impact on the architectural heritage, it also means that human lives and buildings can be protected. The paper will provide real examples to illustrate these cases and will attempt to outline the conservation principles required to protect vulnerable structures, such as those earthen constructions or mud mortar brick or stone masonry built in seismic areas.

Terra 2008. The Tenth International Conference on the Study and Conservation of Earthen Architectural Heritage

(2007). Terra 2008. The Tenth International Conference on the Study and Conservation of Earthen Architectural Heritage. Conservation and Management of Archaeological Sites: Vol. 9, No. 1, pp. 49-53.

Our Earthen Architectural Heritage: Materials Research and Conservation

AbstractEarth construction is the oldest and most universal architectural expression on our planet. The most ancient human settlements were built with raw earth, and even today at least 30% of the world's population still lives in earthen homes. The conservation of earthen architecture depends of two aspects of a global strategy. One part involves intervention to preserve existing structures, and the second involves continuing to use the construction methods and materials in contemporary and future building practices. Traditionally, earth construction has been approached in an empirical way. Only recently have those involved in the field felt it necessary to develop a specific materials research attitude. This has resulted in major technological progress over the last 20 years. The wide range of building systems emphasizes the technological diversity of earth construction. This article presents a historical perspective, along with a review of the characteristics of earth as a building material, stabilization processes, and construction methods, and a report on an ongoing research program aimed at identifying and characterizing the fundamental binding mechanisms responsible for cohesion properties in earthen construction.