Mid Sweden University

Due to the vast environmental impacts related to the construction industry and conventional reinforced concrete (RC) techniques, this paper set out to find out if an upgraded Adobe (mud-brick) technique could potentially be a sustainable alternative for typical residential dwellings in the canton of Orotina, Costa Rica. In doing so it focused on key Adobe properties to address the high seismicity and tropical climate of the location. Adobe techniques show considerable improvements in seismic properties when reinforcement techniques, similar to those in conventional construction, are employed to the masonry. The reinforced Adobe showed no signs of structural failure after testing on a seismic table at maximum capacity (magnitude 10L EQ), so within the limitations of the test it could possibly be a suitable approach for the region. Improved performance in Adobe masonry material was seen during diagonal compression strength (DSC) and dry compression tests; additives effectively controlled dry shrinkage and micro-cracking, key factors in the masonry’s strength. Especially when lengthy natural fibers like ichu and bagasse are used as additives, providing masonry with strengths above Peru’s recommended seismic resistance thresholds. In terms of indoor thermal comfort levels, Adobe structures show better and more consistent comfort levels throughout the entire day as opposed to RC. This suggests that Adobe structures are more efficient at buffering the outdoor temperatures thus very effective at maintaining a constant comfortable indoor temperature, which is preferable in the canton of Orotina. In terms of seismic resistance and thermal comfort, based on the assessment of the results and with careful design planning, an upgraded Adobe technique seems to be a suitable alternative technique in the canton of Orotina and the country of Costa Rica. Even though RC is inarguably superior to Adobe in terms of seismic thresholds, it is deemed excessive for what is needed for an average residential dwelling; as well as not sustainable for an already stressed and depleted environment as opposed to Adobe. Arguably adobe could help relieve some of the increasing construction demand in the country and at the same time aid in lowering the environmental impacts of the construction industry. Costa Rica currently prohibits the Adobe technique in its building code but it could benefit in following Peru’s lead of controlled experimentation and development of the Adobe technique in order to re-introduce this sustainable building method for average dwellings.