Session: 03-20-01: Manufacturing: General

Paper Number: 143309

143309 - Thin-Shell Concrete Quasi-Spherical Small Buildings: Low-Cost, Low-Earth-Impact, Global Shelter 

Humanity needs a billion houses and other durable, low-cost, low-Earth-impact, insulated, Earth-shelterable, small buildings, for protection from extreme weather and heat.  With thin-shell concrete, quasi-spherical, on-site-built, houses and other small structures we can rapidly enclose, insulate, and  finish about one enclosed per five days per three-person crew, anywhere on Earth, at less than one-fourth the CAPEX and OPEX of less-durable stick-built or prefab contemporary substitutes. Service life and threat survival is far greater; multi-decade LCC lower.

Quasi-spherical, thin-shell concrete small buildings -- limited to large radii of curvature -- are optimum, with low CAPEX and OPEX providing very low LCC. This advanced manufacturing method is probably ideal for ~ 5 to 6 m equatorial diameter buildings, perhaps to 8 - 10 m diameter, and morphing to elongated "sausage" shapes for larger buildings with some straight wall to accommodate interior finish and furniture. Imagine adding center "barrel vault" sections. Such morphing allows maintaining large radii of curvature for thin-shell strength and resilience as a "monococque" structure.  

Humanity now needs a billion housing units, and a billion other small buildings for shelter, storage, schools and clinics -- all with low CAPEX, OPEX, long-term Earth impact -- and with great durability and long service lives. Quasi-spherical, thin-shell concrete is the best advanced, on-site manufacturing method for them all. AASI will launch that global industry with Phase 1 NSF research (pending).  Emulators will quickly proliferate our commercial success, from methods and systems developed in Phase 2, for broader worldwide Earth impacts.

Earth's Global Climate Change (GCC) emergency requires humanity to stop building costly, complex, weak, flammable, toxic, "stick-built" small buildings.  We must invent and proliferate structures able to withstand and protect people from weather extremes, fires, seismic shocks -- with small Earth impact, using little material and energy -- and strong enough for protective total Earth burial.  Quasi-spherical, thin-shell ~ 2 cm thick, concrete small buildings -- limited to large radii of curvature -- are ideal, anywhere on Earth. This advanced manufacturing method is probably ideal for ~ 5 to 7 m equatorial diameter buildings, perhaps to 10 m diameter, with morphing to elongated "sausage" shapes for larger buildings with some straight wall.   

Our company, Alaska Applied Sciences, Inc., Juneau, will develop and commercialize an innovative, on-site, rapid, economical, and benign construction methods and materials system for them. We will build on unique research at University of Arizona on compatibility of new, GHG-emission-free and carbon-neutral cementitious materials with carbon fiber epoxy grid primary reinforcement, to determine strength and flexural properties of thin-shell concrete samples made from them.  Following -- in Juneau, Alaska -- we will research ultimate strength of scale-model complete buildings enabling global engineering for safe, economical buildings designs, permits. Intellectual novelty, value:  web and lit searches find no global research on these materials nor structures. Phase 1 de-risk:

1.  Unique ultrasonic testing for compatibility of novel GHG-emission-free or carbon-neutral cementitious materials with carbon-fiber-epoxy primary reinforcement grid, by Chomarat C-grid and others, plus popular fibers and amendments, in thin-shell (~ 2 cm thk) concrete specimens.

2.  Prove forming system, for ring and shell, to create a strong, resilient, monococque structure.

3.  Determine ultimate strength, failure modes for complete, scale-model, thin-shell concrete houses and small buildings in typical real-world static and dynamic loads; yield engineering design data.

4.  Design and test a strain-gauge-based, hydraulically-activated, automatic stress adjusting system for Earth-coupling of base ring: preserve thin-shell monococque strength, eliminate foundation.

About 3 cm of interior-sprayed closed-cell UR foam insulation quickly encapsulates wiring and plumbing, while perfectly insulating without thermal bridging . A thin sprayed plaster or mortar coat protects the foam and completes interior finish, closure, and inhabitability, in a few days, at low cost and long-term LCC.

The stick-built rectangular-solid building is obsolete in today's GCC-driven world. We need a better path to shelter. That's the global problem we are solving with innovative advanced on-site manufacturing.     We must develop a rapid, economical, and benign construction methods and materials system for these quasi-spherical thin-shell concrete structures to lower cost, speed access and delivery, thus adding value.

Presenting Author: William Leighty Alaska Applied Sciences, Inc.

Presenting Author Biography: - BSEE, Stanford, 1965
- MBA, Stanford, 1971
- Collins Radio Company:
 Marketing Engineer, 1966-67
 Field Engineer, Thailand and Vietnam, 1968-69
- State of Alaska, Budget Analyst
- Small business owner, Juneau, Alaska, 1972 - present
 Alaska Applied Sciences, Inc. www.AlaskaAppliedSciences.com
- Director, The Leighty Foundation, Earth Protection Program, Juneau, Alaska, 1990 - present,
www.LeightyFoundation.org/Earth.php

Authors:

William Leighty Alaska Applied Sciences, Inc.