"At the Intersection of Beauty and Strength: Earthen Structures that Survive Earthquakes" http://www.scaruffi.com/leonardo/sep2012.html

1. Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

2. Huacas, enormous monuments in
Peru built entirely of individual adobe
blocks – Huaca Pucllana in Lima, Peru,
500 AD
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

3. Chan Chan, Chimú Empire, near Trujillo, Peru – 850 AD until 1470 AD
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

4. Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

5. Elsewhere in the Americas – Taos NM, San Francisco de Assis Church, 1816
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

6. Great Mosque at Djenné, Mali – 1907 – largest adobe structure in the world
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

7. Sun-dried mud bricks (adobe, called “ferey”), mud mortar,
mud plaster on exterior. Bundled palm protrusions serve as
scaffolding for maintenance and access.
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

8. cob bird’s nest
cob “fish” lantern
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

9. “lipan” earth embroidery in Gujarat, India
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

10. Arg-é Bam, Iran, adobe city and citadel in use 500 BC to 1850 AD
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

11. After 2003 earthquake – erosion + ground acceleration = over 75% damaged
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

12. Areas of greatest seismic activity around the world:
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

13. Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

14. De La Osa Adobe, Encino CA, 1850 - damaged by Northridge Earthquake, 17 January 1994
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

15. …not to mention the billions, by some
estimates close to 1/3 of the world’s
population, living in adobe constructions
and susceptible to seismic disasters.
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

16. What is the problem?
earthquake “force”
ground acceleration
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

17. What are some solutions?
1. horizontal reinforcement of adobe
masonry
2. high fiber content
3. confinement
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

18. 1. Fabric reinforcement for
masonry walls:
• prevents the primary crack
formation
• transfers stresses in
mortar to other parts of
the wall by bonding well to
the mortar
• forces small cracks to form
throughout
• can be VERY inexpensive –
synthetic felt, burlap etc
• allows overall wall to
deform greatly
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

19. Felt fabric reinforcement allowed wall to
stay together under large loads
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

20. 2. High fiber content in cob works similarly:
• transfers stresses in cob to other parts through spread and bond of fibers
• forces small cracks to form throughout
• can be VERY inexpensive – straw
• allows overall structure to deform greatly
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

21. 3. Confinement on exteriors of adobe or cob wall:
• do not attempt to change behavior of wall components
• contain and control wall material during seismic activity
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

22. Actual implementation of these techniques (1 & 2):
Concept watercolor for bamboo-cob composite building by
Massey Burke. Clarks Island, Clear Lake, CA
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

23. Model of interior bamboo
structure
Model of bamboo-cob composite
building
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

24. Many names, one idea:
quincha, wattle-and-daub,
bahareque
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

25. USF students & community building together
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu

26. Many thanks to:
• University of California at Berkeley, where
the fabric reinforcement studies were
conducted (Claudia Ostertag, Bill
MacCracken, Jeff Higginbotham)
• University of San Francisco and Santa
Clara University, where the heavy straw
clay and bamboo studies were, and
continue to be conducted (Massey Burke,
Mark Aschheim)
• Pontificia Universidad Católica del Perú,
where the greatest amount of study on
earthen structures is conducted (Marcial
Blondet, Daniel Torrealva)
Musgum earthen architecture, Cameroon
Hana Mori Böttger · Architecture & Community Design hmori2@usfca.edu