Behavior of masonry in the Northridge (US) and Tecomán–Colima (Mexico) earthquakes: Lessons learned, and changes in US design provisions

The Northridge earthquake (near Los Angeles, CA, USA, January 17, 1994) and the Tecomán–Colima earthquake (near Manzanillo, México, January 21, 2003) have increased our knowledge of the behavior of masonry buildings in significant earthquakes, and also have led to changes or proposals for changes in US masonry design provisions. In this paper, the masonry code-development process in the US is briefly reviewed, with emphasis on the fundamental role of the Masonry Standards Joint Committee (MSJC). The Northridge and Tecomán–Colima earthquakes are discussed, with emphasis on the behavior of modern engineered masonry. Lessons learned from those earthquakes with regard to masonry are summarized, and the related evolution of MSJC design provisions for the US is discussed.