H. Kit Miyamoto, Ph.D.1Amir SJ Gilani, Ph.D.2, D. Sonda3, and A. Wada4

1President, Miyamoto International, West Sacramento, CA, 95691
2Senior Associate, Miyamoto International, West Sacramento, CA, 95691
3Principal, Miyamoto International Italia, Milan, Italy
4Professor Emeritus, Tokyo Institute of Technology, Tokyo, Japan

For full access to this technical paper click here and we will contact you shortly.

Historic and heritage building present a unique class of structures. These buildings form a cultural
pillar of the communities and thus require preservation. However, given their vintage, they have
sustained severe damage and collapse in recent earthquakes, including in Italy (2009), Haiti (2010)
and New Zealand (2011). The main vertical and lateral load bearing members for these buildings
is typically comprised of unreinforced stone masonry (URSM) walls. These walls have
experienced both in-plane and out-of-plane failures, leading to the collapse of the structures.
Given that the walls have little lateral capacity, it is critical to limit the input forces acting on
them. In addition, these structures do not have a well-defined load path or diaphragm for seismic
loading. A proposed mitigation strategy combining seismic isolation and superstructure
intervention is discussed to address these deficiencies. Advanced nonlinear global and local finite
element analysis is used to assess the efficiency of the proposed retrofit. The proposed method
significantly reduces the level of seismic excitation acting on the existing walls and limits the
superstructure retrofit, and thus preserves the historical features of the structures. Application of
this technique to two Cathedrals in Haiti is presented.