Coastal Architecture and Engineering

Although we are ostensibly working on more novel concepts, it is important to understand current techniques and the creativity and resourcefulness of the coastal peoples.  Among creative architectural aspects we experienced on our way to Rockefeller were creative ways to avoid or minimize damage from coastal flooding, edible landscapes, techniques to enjoy the beauty of the coastal environment, and structural and stability related techniques.

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 These rings are 60" in diameter, 30" high, and 9" in wall thickness.  They are in a high wave energy zone and appear fairly stable.  They are supported by gabion mats with expanded clay substrate.  These type of units (or ideally some with less total mass) could "grow" a structure in multiple ways: they can grow oysters, barnacles, etc, which can eventually strengthen and stabilize the structures; they can grow in terms of supporting the local ecology; they can grow vertically, even if they sink; and they can accrete sediment (both inside the rings and in the low energy "settlement" zone behind the breakwater), and hence "grow" land. This land may spontaneously grow plants, or could be planted to appropriate vegetation to further stabilize and encourage accretion in appropriate zones.

 Rockefeller refuge is a beautiful place, and their buildings are built on nominal 12" diameter posts sunk well into the ground.  Although the ground itself is a sedimentary clay with fairly low bearing strength, when the posts "set" in the mud (adhere to the soil by frictional contact with the soil), they can support these buildings which allow a lovely view of the vegetation (live oaks and spanish moss shown here), as well as additional protected parking or workspace below the structure.  This general technique is well accepted in the area.

 This tiny (but locally famous) grocery displays another simple technique: basically this is fill with a concrete cap, a variation of slab on grade that gains the building a few feet of elevation to avoid modest flooding.  The metal building is simple and pragmatic if not overly aesthetic.

At a research site in a waterway in the Rockefeller refuge, a treated wooden post has been in place and even provides a local benchmark (recalibrated every two years by high accuracy GPS).  The calibration shows this post is quite stable over time.  Again, the "skin friction" with the underlying sediments keep the post stable and able to hold a modest load, perhaps enough for a building to be mounted on similar posts.

Up the road, we visited with a team installing posts for a new building. These posts were nominal 12", "fat end up" (to minimized expanding the holes), installed by first auguring with a tractor mounted augur (~6' deep), then pounding them in to a depth of about 18' by using a crane mounted pounding device.  This leaves about 12' of the 30 foot length protruding to be used to mount the superstructure.  The crane had installed one post about a foot too deep and was trying to remove the post.  The crane pulled, tipped (and scared us), attempted a couple more times, then decided to leave the post.  The posts seem able to support at least a couple thousand pounds or more each, based on this little test.

An alternative technique was used to provide very good support (enough to drive the car to the second floor as shown!) here:  this was 10" steel posts driven in to a depth of about 10 feet, spaced on about 8 foot centers, with steel beams welded between to make a single superstructure on which to build the house.  The structure seemed very stable and had a pleasant ambiance including a 12' deep back porch with hummingbirds and a view of the nearby grazing land and wetlands.