Improved seismic-resistant design of adobe houses in vulnerable areas in Peru : Raising seismic awareness in an Andean community

Abstract: During the last decades, many seismic reinforcement techniques of adobe houses have been developed. None of the techniques has however reached out to the people in need, mainly due to high costs. To prevent unacceptable seismic risks in rural areas, it is necessary to develop technology transfers along with training and educational programs. PUCP (The Pontifical Catholic University of Peru) has started a training project on earthquake resistant adobe constructions, addressed to inhabitants in an Andean community. Their attention is set at this time, to the district of Pullo, which is located in a highly seismic area. 80 % if the population is living in adobe houses and more than 50 % of them are living in poverty. PUCP is leading an extensive project, which objectives are to work with people in order to make them aware of the vulnerability of unreinforced adobe houses, and practically lean the technique of reinforcement with nylon ropes, called halyards. On the 24th of August 2014 an earthquake measuring 6.9 on the Richter scale hit the district of Pullo. The situation in Pullo was evaluated to be heavily affected but concluded not to be urgent. Therefore a training project instead of reconstruction program was planned. The initiative aimed to raise seismic awareness among the people, and transfer knowledge on how to build seismic-resistant adobe homes. The work included in this report is part of the long term project at PUCP. Firstly, the acquired knowledge on adobe construction’s techniques, seismic effect on adobe houses built using different methods is included. A more detailed description of the new developed construction system is introduced, which was obtained by the experience gained by direct part-taking on the training project. The training and experimental stage of the project development included experimental testing on different constitutive parts of the constructive system, such as reinforcing rope-knots, manufacturing of adobe scaled building models, training of a portable shacking table, and socio-anthropologic experiments performed in situ. The use of modified tensile experiments, visual observation led to a recommendation of two knots, which proved to bring about the best structural performance in relation to seismic resistance. The manufacture of scale-building models in combination to the portable shaking table proved excellent results for direct comparison of structural behavior as well as in-situ educational purposes, instructing the people of Pullo about the new system. The latter added a direct and deep impact on the people, which results are to be shown in the future, by the follow-up of the project and the construction of new houses using the developed system.