Adobe housing in El Salvador: Earthquake performance and seismic improvement

Abstract

Adobe is the predominant housing material in rural El Salvador, due mostly to economic advantages and ease of construction. The high seismicity of El Salvador has repeatedly exposed the vulnerability of traditional adobe housing to the forces of earthquakes, as spectacularly demonstrated in the severe earthquakes of 2001. This paper presents the features of traditional adobe housing in El Salvador, including construction techniques and distribution, followed by a discussion of the performance of adobe buildings in recent earthquakes in El Salvador. The impact of the 2001 earthquakes is demonstrated by statistical data, which also reveal the severe housing defi cit in El Salvador. Common damage patterns evident in earthquake-affected adobe buildings are detailed, with emphasis on the failure mechanisms and exacerbation features. These aspects are then linked to a presentation of improved seismic design and construction techniques; seismic retrofi tting and damage repair systems for adobe structures are also considered. Finally, the obstacles to reducing damage to adobe houses are presented, and some key recommendations for adobe strengthening in El Salvador are discussed, which involve both social and technical solutions.

Control of hazard due to seismicity induced by a hot fractured rock geothermal project

“…The traditional building types are adobe and bahareque. Adobe is sun-dried clay brick and the very high mass-to-strength ratio of houses constructed from this material makes them highly vulnerable under earthquake shaking (Dowling, 2004). Bahareque is a form of wattle-and-daub, with timber vertical members and a horizontal cane (barra de castilla) lattice filled with mud and covered with plaster, comparable to the taquezal system used in neighbouring Nicaragua, as well as to the Peruvian quincha system and the Japanese shinkabe.…”

Expansión lineal y punto de saturación de las fibras de la Guadua angustifolia Kunth

“…Su uso se ha dado gracias a los conocimientos y téc-nicas aprendidos a través de la experiencia, pero poco ha sido el desarrollo ingenieril del material, lo que ha conducido en muchos casos a un uso inadecuado o incorrecto (Correal, 2016). Particularmente, la industria de la construcción ha utilizado la G. angustifolia para la elaboración de viviendas o puentes, los cuales han sido construidos en su mayoría sin ningún tipo de diseño estructural y con baja supervisión técnica (Dowling, 2004;Luna et al, 2011), conduciendo a errores que han llevado al colapso de estructuras. Desde comienzos del nuevo milenio, Colombia ha liderado la elaboración de normas que han permitido entender muchas de las características de la guadua, con el fin de que las industrias que utilizan el material puedan incrementar su uso y mejorar su comportamiento, para así poder darle un mejor y seguro aprovechamiento (Gatóo et al, 2014).…”

Dynamic Testing and Analysis of Adobe-Mudbrick Structures

“…The predominant failure modes of traditional adobe-mudbrick houses subjected to earthquake loads are vertical corner cracking at the intersection of orthogonal walls, and horizontal, vertical and diagonal cracking due to out-of-plane flexure (Zegarra et al, 1999;Flores et al, 2001;Dowling, 2004b). This commonly leads to overturning of walls and collapse of the roof (fi gure 1).…”