Most historic buildings in El Salvador are made out of
adobe, a type of earth masonry that is non-engineered and extremely weak
against earthquakes. This study was conducted to find the best solution for the
retrofitting of these buildings. A 150-years-old adobe building was evaluated
considering three retrofitting solutions: Polypropylene band wrapping, Backside
wall affixing, and RC frame affixing. The analysis was conducted using three
methods (JBDPA Guidelines, capacity spectrum method, and response history
analysis), and two levels of seismic demand. The Polypropylene band wrapping
solution was not enough for a building this weak and a site with such
seismicity. The RC frame affixing solution worked, but it requires partial
demolition works and causes extensive cracking on the walls. Finally, the
Backside wall affixing technique presented a failure mode that protects the
walls from damage while avoiding an aggressive alteration of the building in
the low seismic demand level.
Keywords: Adobe, Retrofitting, Historic building, PP-band, Backside Wall.