Training in Earthquake Resistant Construction With Adobe in the Peruvian Andes

Malena Alessandra Serrano Lazo, Marcial Blondet, and Álvaro Rubiños, Pontificia Universidad Catolica del Peru (Charlotte, NC): Training in earthquake resistant construction with adobe in the Peruvian Andes

It is estimated that half the people in the world live in houses made with adobe (sun dried mud bricks) or rammed earth. In Peru, there are more than two million houses made of these materials (35% of the total houses; INEI 2007), in which almost 9 million people live, mainly because they cannot afford to purchase industrialized construction materials. Although adobe houses are cheap to build and thermally comfortable, their seismic performance is very poor: the heavy, weak and brittle earthen walls are not able to resist the seismic forces and the building suffers significant damage or collapses, usually with tragic loss of life. Therefore, researchers at the PUCP and other institutions have developed many different reinforcement techniques over the years as an effort to improve the structural safety of earthen houses located in seismic areas. But, sadly, none of the techniques developed for rural communities have been adopted massively, mainly due to high cost and lack of diffusion. As a consequence, most rural communities live under unacceptable seismic risk conditions and it is urgent to develop technological transference tools and training programs for earthquake resistant earthen construction.

There is an on-going project to train communities on the construction of safe and decent earthen houses in seismic areas at the PUCP. As a study case, it has been selected the district of Pullo: a small rural community in the Peruvian Andes where more than 80% of its habitants live in adobe houses and more than 50% are considered to live in poverty or extreme poverty conditions. The project consists on working with the people of the community, helping them improve their housing conditions by acquiring the ability to do so on their own. A simple low-cost reinforcement is proposed (nylon ropes) in order to increase acceptance among the population and the training program is divided into three phases to ease the learning process: 1) Raising the community´s habitants awareness of the high seismic vulnerability of their non-reinforced adobe houses and introducing the possibility of building earthquake resistant adobe houses; 2) Training the community in the rope mesh reinforcement technique and applying that knowledge through the building of a community center with the collaboration of all habitants; 3) Following up the community to assess the success of the project and propose improvements on new training programs. The success of the project will be assessed by the acceptance of the reinforcement technique among the population, which would be measured by the improvements in the housing conditions of the community (repaired houses and constructed new houses using the rope mesh reinforcement). It is expected that if the project succeeds, the results could be replicated in any other community located in seismic areas where construction with adobe is prevalent.

This paper will present the materials, communication tools and training tools developed during the project and used to train rural communities on the construction of safe and decent earthen houses in seismic areas. Scale seismic simulations have been designed using a portable shaking table to prove the effectiveness of seismic reinforcement in adobe houses, both for vulnerability awareness as for learning the rope mesh technique. Additionally, an earthquake resistant adobe construction manual and a motivational video, including testimonials, have been updated to include the proposed reinforcement. Finally, the paper will describe the on-going experience in training the Pullo community and the conclusions obtained so far about the success of the training program (acceptance to the proposed rope mesh) and the possibility to replicate the project in other communities under seismic risk.

Additional Materials: