Spanish colonial missions and Mexican rancho and pueblo adobe structures are among California’s earliest existing structures and the only above-ground remains of the state’s original settlement by the Spanish and Mexican people. The Northridge earthquake of January 17, 1994, resulted in tragic losses to a number of these historic adobe buildings. The earthquake also provided a rare opportunity to assess the damage that can occur to such structures as the result of a large earthquake. The intent of this study—part of the Getty Conservation Institute’s long-term commitment to researching conservation measures appropriate for historic adobe structures—was to survey the damage to buildings and make an informed evaluation of their seismic performance. The ultimate goal was to use the lessons learned from the Northridge earthquake and the results of retrofit research to help owners, building officials, cultural resource managers, architects, and engineers to understand the risks earthquakes pose to historic adobe buildings and the necessity for taking considered action to limit those risks.

• Foreword
• Preface
• Chapter 1 Background Information
• Chapter 2 The Northridge Earthquake: Characteristics and Measurement
• Chapter 3 Damage Typologies and Assessment
• Chapter 4 Rancho Camulos
• Chapter 5 Andres Pico Adobe
• Chapter 6 De la Osa Adobe
• Chapter 7 Leonis Adobe
• Chapter 8 Lopez Adobe
• Chapter 9 Convento at the San Gabriel Mission
• Chapter 10 Lopez-Lowther Adobe
• Chapter 11 Pio Pico Adobe
• Chapter 12 Other Adobe Buildings
• Chapter 13 Analysis and Summary
• Glossary
• References

E. Leroy Tolles is principal investigator for the Getty Seismic Adobe Project.

Frederick A. Webster is a principal with Earthen Building Technologies.

Anthony Crosby is a historical architect with the National Park Service.

Edna Kimbro is an architectural conservator and historian specializing in the preservation of Hispanic-era buildings and material culture.