Historic rammed earth structures in Spain : construction techniques and a preliminary classification.

Conservation and repair of historic rammed earth sites should only be undertaken if there is a good understanding of the consequences of any intervention technique. Until recently there has been little interest in the characterisation of historic rammed earth construction, yet it is only with this understanding that successful conservation strategies can be adopted. A survey of around 60 historic rammed earth sites in Spain constructed between 967AD and 1837AD has recently been undertaken. While all the sites are built primarily in rammed earth, the construction techniques and state of repair vary greatly. The high density of historic rammed earth structures in the Iberian peninsula is likely due to the Muslim presence there from the 8th century onwards. Initial expansion, a period of civil war and eventual defeat by Christians led to the construction of a large number of fortifications, many constructed in rammed earth. A famous example is the Alhambra at Granada, but there are hundreds of smaller sites throughout Spain. By the end of the 15th century Christians had replaced Muslims through most of Spain, but rammed earth continued to be used in both vernacular and monumental architecture. Examples of historic construction techniques are presented and common features of historic rammed earth construction are identified. A classification is outlined and a clear development of the rammed earth technique is observed

Analysis of Tapial structures for modern use and conservation

Tapial is an ancient form of rammed earth wall construction found in many parts of the world. In medieval Spain, Tapial was used in the construction of some large and complex structures, some many-storied. That these buildings remain standing (many remaining in use) is an indication of the durability of this form of construction, and is perhaps related to the climatic conditions found in central Spain. This paper describes an engineering study into an important structure in the Aragon region, significant parts of which are constructed in medieval Tapial, as well as other forms of construction. The aim of the study is both to improve understanding of the nature of this structure and to provide guidance on methods of preservation and new construction

Chronological description of the spatial development of rammed earth techniques

Rammed earth has been used by man for thousands of years and is currently experiencing a revival in some parts of the world as a result of its inherent sustainability. Historic rammed earth structures are scattered around the world, and much information can be derived from these structures to inform the development of modern rammed earth. This article provides a chronological study of rammed earth distribution through observation of monumental buildings to aid the study of this building technique. It is shown that the rammed earth technique is likely to have originated independently in China and around the Mediterranean, and spread through the movement of people and ideas to many other parts of the world. Through observation of historic rammed earth sites, geographic and climatic limits can be placed on the extent of rammed earth. The different ways rammed earth has been used over time are explored, culminating in its current incarnation as a sustainable building material

The strength of unstabilised rammed earth materials

Rammed earth is a manufactured material comprising sand, gravel and clay, which is compacted between forms to build walls. Primarily a historic method of construction, it is now receiving considerable interest worldwide owing to its zero reliance on materials such as cement, and its potential for recycling. Despite its longevity, the source of its shear strength is poorly understood. This paper presents initial laboratory test results that point to the main source of strength in rammed earth being suction, and indicating that recent advances in unsaturated soil mechanics may also be applied to this material

First International Conference on Rammed Earth Construction: report

In February 2015, the University of Western Australia organised the First International Conference on Rammed Earth Construction. The event was a major success with participants from 11 countries. The participants were representatives from the research (scientists, professors, students) and industry worlds (engineers, architects, builders). The conference provided the unique opportunity to present recent advances in rammed earth research, innovative construction practices and sustainable projects in different countries. It also provided the opportunity to discuss the current issues experienced by the rammed earth industry around the world and to create collaborations between research institutions. This paper presents a summary of the discussions held at the forums of the event. It aims to disseminate the priority research topics identified at the conference and to increase awareness of the difficulties currently experienced by the rammed earth industry and by academia

Historic rammed earth structures in Spain: construction techniques and a preliminary classification

Conservation and repair of historic rammed earth sites should only be undertaken if there is a good understanding of the consequences of any intervention technique. Until recently there has been little interest in the characterisation of historic rammed earth construction, yet it is only with this understanding that successful conservation strategies can be adopted. A survey of around 60 historic rammed earth sites in Spain constructed between 967AD and 1837AD has recently been undertaken. While all the sites are built primarily in rammed earth, the construction techniques and state of repair vary greatly. The high density of historic rammed earth structures in the Iberian peninsula is likely due to the Muslim presence there from the 8th century onwards. Initial expansion, a period of civil war and eventual defeat by Christians led to the construction of a large number of fortifications, many constructed in rammed earth. A famous example is the Alhambra at Granada, but there are hundreds of smaller sites throughout Spain. By the end of the 15th century Christians had replaced Muslims through most of Spain, but rammed earth continued to be used in both vernacular and monumental architecture. Examples of historic construction techniques are presented and common features of historic rammed earth construction are identified. A classification is outlined and a clear development of the rammed earth technique is observed