Saint John Baptist Cathedral of Miragoane is an historic building of great importance to Haitians. To protect this heritage building originally constructed in the 1880s using concrete floors with unreinforced masonry and stone walls over stone masonry foundations, Miyamoto provided a high-performance seismic rehabilitation and retrofit using base isolation. Originally constructed of rock and mortar, the cathedral but will be supported by 54 triple-pendulum base isolators to protect it in a major seismic event.
The base isolators will “float” the building so its columns, arches and walls to keep the structure from being frantically rocked in an earthquake. In conjunction with these isolators, a 12-inch moat around the building will accommodate movement. Base isolation is a modern technique that is being applied to ancient structures — a collaboration that saves the old with new technology.