Coastal Engineering - Amphibious Housing

Floating Foundations / Bases

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The foam, EPS, that is used for the bases of these homes is supported by water; which makes it virtually unsinkable. EPS consists of a variety of “pearls” or a closed cell structure, which consist of approximately 98% air; this accounts for the buoyancy. Tests have shown that fully submerged EPS only absorbs about 7% water. Because of the potential degradation due to chemicals and insects; the foam is covered with concrete and polyurea. This helps to reinforce the structure of the home [7].

EPS is extremely easy to design since it is built directly on the surface of the water; therefore the only constraint on the size of a floating structure is the formation of the concrete. The larger the floating structure, the more stable the structure will be. 

Depth of the structure is less than half of a concrete shell. 
Made of only one type of material is great for recycling. This highly recyclable material then become reusable, making a contribution to environmental conservation.  Additionally, the does not contain CFC's and do not leech into the environment.   The Army Corps. of Engineers has tested EPS and estimated the lifespan of an exposed EPS foundation to be 20 years.  However, by adding a 1.25" coating of polyethylene the lifespan can be tripled or quadrupled yielding a usable cycle of up to 80 years
[16]
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Another advantage of the water support  is that it is possible to construct the structures of many different dimensions. Additionally, there is no soil stability issues to deal with since there is a uniform liquid beneath the foundation with known properties.  

Construction begins with a work floor consisting of EPS sheets are glued together and constructed on the water surface. The grid pattern used to develop the floating base is designed before the home is built based off of the estimated size home
 [8].