Due to growing interest in sustainable building, University of Southern California faculty member Madhu Thangavelu recently met with Nader Khalili to discuss Khalili's role, as an architect and inventor, in the development of innovative materials and methods of construction.

Madhu Thangavelu:     After having specialized in the design of high rises in the 1970s, you turned your attention to the research and development of ceramics and superadobe/superblock building technologies based on indigenous Middle-Eastern building traditions. What prompted you to propose the use of these technologies for lunar and planetary construction to NASA? Nader Khalili:     When I left my high-rise architectureal design practice, I set out on a five-year journey through the Persian deserts to explore the potential of clay as a building material that could be used to house the Earth's masses--there were then 800 million people in the world without adequate shelter; that number is now 1.2 billion. In those deserts, there are no resources except earth. Trees are too precious to cut, and constructing walls provides more shade and consumes less water. During those five years, I integrated my knowledge of high-rise and prefabricated building technologies with thousands of years of accumulated human knowledge about earth architecture and ceramics. This synthesis of high-rise and traditional earth building methods resulted in the new technologies of ceramic and superadobe/superblock construction.

      I faced some new challenges in 1984 when I was among those invited to the first NASA-sponsored symposium, "Lunar Bases and Space Activities of the 21st Century," held at the National Academy of Sciences in Washington, D.C., to propose new technologies for possible use in the construction of lunar bases, but the fundamental problems were very similar. There are even fewer resources on the moon than in our deserts, and the climate is much harsher.

There was not known to be any water then, and there is no atmosphere; therefore, there is no oxygen to fuel the fire needed to manufacture ceramics. The moon's surface temperature range varies from 261 degrees F (127 degrees C) to -279 degrees F (-173 degrees C), and the potential effects of solar particle radiation and meteorite impact had to be considered. Yet on the moon--as on earth and, indeed, throughout the solar system--timeless materials and principles exist. An understanding of the concept of the unity of the elements makes the use of these materials and principles in the integration of tradition and technology with the laws of nature possible at many levels of microcosm and macrocosm.

      My paper "Magma, Ceramic and Fused Adobe Structures Generated In Situ," described the timeless architectural forms of the arch, the vault and the dome; their structural principles; and the possibility of constructing them by transforming lunar dust/regolith into liquid magma using solar fire to cast the buildings. It also introduced the concept of a building material I then called "Velcro adobe," which is now referred to as superadobe/superblock, which was referred to in the Journal of Aerospace Engineering with these words:

      Two main materials and methods utilizations of moon dust for shielding or generating structures are in the forms of automated or manually packed soil covering, or Velcro adobe, and fused lunar adobe. Soil packing covering in flexible dry-adhering containers (Velcro adobe) will utilize unprocessed regolith for both structures and shielding. Packed Velcro adobe in flexible containers can be used to construct structures using corbels, dry-packs and leaning arches. In single- and double-curvature compression shells, the dry-adhering containers' texture will allow the tightness of consecutive rows, in the case of a vault, or rings in a dome, to hold up the structures in space during construction. Neither type of structure needs centering or form-work. Velcro adobe can be used in conjunction with other, more conventional, structures, mainly for shielding purposes.

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