Adobe Buildings in Earthquake Areas

Historic vs. Modern Adobe

• Archaeologists trace the use of adobe back to 8,000 B.C. In most cases, they find adobe in "non-engineered construction," meaning homemade, without the benefit of architects or engineers. The more modern an adobe structure, the more likely that it is designed with sound architectural principles in mind. Risk assessments of modern earthquake damage in states such as California clearly indicate the measures that must be taken in order to build with adobe in earthquake areas.

The Issue of Moisture

• The main fear with adobe buildings in the case of an earthquake is that they will simply turn back into the mud from whence they came and slide down the mountain or hillside into nothingness. According to NASA, earthquakes may be followed by floodwater within days or weeks. Subsequently, reinforcement of adobe with other materials such as concrete or steel is more and more prevalent -anything that helps to hold the building together, the lower the better.

Building Codes

• The myth that adobe building should only take place in arid climates such as Arizona, New Mexico, and parts of Texas is not true. People use adobe all the time in wetter zones and even earthquake-prone areas such as parts of California and Mexico. It is important to follow the building codes for each state stipulating the mixture of adobe and concrete and/or asphalt for maximum strength and resilience.

Seismic Engineering

• It is possible to add seismic reinforcement to both old and new adobe buildings to make them less likely to collapse at the corners during an earthquake. You can place bands of concrete or timber around the beams of the ceiling, as well. Strengthening walls with chicken wire, barbed wire, bamboo, or steel rods is also a proven technique. New adobes should not be more than one story high in earthquake areas, as a general rule.