The other architecture: From natural caves to excavated housing

Excavated towns are an attractive example of underground urbanism that managed to solve, in a very interesting way, thermal problems thanks to natural ground inertia or transition spaces. The aim of this paper is to show the typological evolution of excavated dwellings worldwide, as an architectural proposal and urban solution. The proposed methodology provides an analysis of underground architectures from natural caves to excavated housing, focusing on the study of global constructive solutions to specific problems. Thus, architectures as a natural geography correction (horizontal excavation), buried underground architectures (vertical excavation), subtractive architectures (shallow excavation) and combined architectures (mixed excavation) are studied. In conclusion, there are many examples of typological combinations since troglodyte architects tried to adapt the most elementary constructive rules to get greatly enriched results. These proposals of different underground structures deal with each territory and its geographical features, and obtain urban and architectural solutions transferable to current configurations.

Excavated housing in Crevillente (Spain). Constructive and typologycal study

Underground architecture has sheltered man for many centuries, but the current need to emphasize the bioclimatic approach makes the study of excavated housing essential. This traditional construction is a part of the collective human living experience but also a reference in using the natural conditions of each region through simple proposals based on ground thermal inertia. The aim of this paper is to show the typological evolution of the excavated dwelling in Crevillente, in southeast Spain, compared to other worldwide architectural proposals or urban solutions. To show their adaptation to the regional geography and to comprehend both formal and material characteristics of these simple typologies, which do not need extra energy contribution for interior conditioning. This work is part of the doctoral thesis of the author.

Characterization of the instability mechanisms affecting slopes on carbonatic Flysch: Alicante (SE Spain), case study

The studied Flysch sequence of Alicante occupies a widely populated area crossed by main communication routes. The slopes existing on this area usually suffer slope instabilities that cause substantial damage and a very high maintenance cost. In order to assess the type of instability mechanisms affecting these heterogeneous carbonatic slopes, in this paper a wide inventory of 194 Flysch rock slopes has been performed, reporting the existing lithologies, their competence and their relative arrangement and the geometrical relationship between bedding and the slope and the associated instability mechanism. All these data have been jointly used for performing an instability mechanisms characterization. For systematically characterizing the wide type of complex rock exposures existing in the study area, they are divided into basic units referred as lithological pattern columns to which the different observed instability mechanisms are associated. Inventoried instability mechanisms are diverse and sometimes are combined with each other. Rockfalls are a very common instability mechanism associated to the differential weathering and sapping of the marly lithologies which are present in a wide number of geometrical combinations. The other instability mechanisms closely depend on the combination of the geometrical and lithological parameters. Therefore, this work provides a new basic tool which can be easily used during preliminary project stages for knowing the instability mechanisms which can affect rock slopes excavated on carbonatic Flysch heterogeneous geological formations.

Radon measurements in the cave houses of Crevillente (Spain)

This paper focuses on the cave houses of Crevillente (Spain) as a traditional housing experience which takes advantage of local environmental conditions through simple architectural proposals, paying particular attention to the presence of radon gas inside these underground constructions. Our aim is twofold: first, to analyse the architectural conditions of the different excavated typologies found in the municipality and second, to relate them to the existing radon gas levels after checking internal concentration by means of E-PERM® long-term devices placed inside the cave houses in 2011. The measurements corresponding to the main typologies in normal use conditions show that the highest values are 881.9 Bq/m3 in the cave typology, 484.1 Bq/m3 in the cave + attached constructions typology and 373.4 Bq/m3 in the cave + house typology, with geometric mean values of 572.1, 114.0 and 75.5 Bq/m3, respectively. It can be inferred from these results that cave house levels sometimes exceed those included in the 90/143/Euratom European Commission Recommendation on the protection of the public against indoor exposure to radon. The reason why cave houses are more susceptible to radon accumulation in their spaces lies in their direct and permanent contact with the ground where they are located.