A review of local construction practices applied on unreinforced adobe buildings in South America

Abstract

The historical earthquake activity that involved Andean countries in the last centuries makes the seismic risk evaluation associated to buildings in these areas an issue of crucial concern. Planning seismic risk mitigation policies requires an extensive knowledge of the territorial built environment, of the adopted construction techniques and of the adopted anti-seismic presidiums, in particular when applied during the reconstruction processes carried out after destructive events of the past. In this perspective, this paper contributes to the analysis of adobe vernacular buildings, which represent a spread typology in Latin America and the Caribbean, stressing the past construction practices, their fragilities, and the mitigation measures applied till today. To this purpose, the city center of Cusco, in Peru, where residential buildings are mostly made of adobe, is considered as a meaningful field of observation, because of the long history of the center, which allows to recognize also old construction techniques and the additions/raisings applied during the buildings life, as well as due to the relevant historical seismicity, which permits to appreciate the reconstruction processes implemented after seismic events occurred in the past.

Leveraging Life Cycle Cost Analysis (LCCA) for Optimized Decision Making in Adobe Construction Materials

“…According to Cocco et al [5], the hot climate and clayey soil in Argentina have contributed to the development of adobe blocks containing a substantial amount of sand and straw. The production of adobe blocks in the country is characterized by a composition of 60% sand, 27% silt, and 11% clay, along with a noteworthy quantity of straw.…”

“…In contrast, blocks in Bolivia are characterized by a composition comprising 20% sand and silt, 60% clay, and a small proportion of straw. The frigid climate and sandier soil present in the country obviate the need for such measures [5].…”

“…Furthermore, it is worth noting that in South America, conventional masonry constructions predominantly employ adobe and concrete bricks measuring 10 × 20 × 40 cm [5]. This allowed for a detailed cost comparison between the utilization of adobe and concrete bricks.…”

“…Adobe construction techniques depend on the site. For example, adobe buildings in Latin America and the Caribbean have been characterized by relevant seismic activity, which differs between nations because local building cultures, soil types, and climates have led to the development of unique techniques and approaches in each community [5,6].…”

Quantitative Contribution of Timber Ring Beams in the Dynamic Response of Adobe Masonry Structures

“…A recent on-site survey conducted within a Nicosia community, under the umbrella of the ISTOS center along with the subsequent development of seismic maps for the same region, have underscored the heightened vulnerability of adobe structures to collapse compared to other load-bearing counterparts. Notably, adobe construction finds widespread usage in regions of the world prone to natural hazards, including Latin America [5,6], Africa [7,8], the Indian subcontinent [9,10], various parts of Asia [11,12], the Middle East [13,14], and Southern Europe [15][16][17][18][19]. This prevalence extends to encompass approximately 30% to 50% of the world's population, which translates to an estimated 3 billion individuals who either reside in or work within earthen buildings.…”