Categories
Construction Earthbags

Earthbag Technical Report from Nepal

Good Earth Nepal has published this PDF on its site.

Before presenting some highlights I would add that there are a few details which, to my understanding are only correct in the context of typical above ground houses, less so with bermed or underground structures.

“At present, there are over 15,000 Earthbag buildings worldwide with recent Earthbag¬† constructions gaining approval under strict US building codes.

An estimated 55 Earthbag structures built in Nepal survived the 2015 earthquake, in regions ranging from Solokumbu to Sindhupalchok to Kathmandu.

… The main material of an Earthbag structure is ordinary soil obtainable at the worksite.

… A study by the U.S. Federal Highway Administration found that the half -life of polypropylene fabrics in benign environments can be 500 years or more. The
bags themselves have a tensile strength even higher than that of steel, and can resist circumferential forces generated from the weight above.

… An Earthbag building uses its own weight to anchor itself to the rubble trench foundation. Since the superstructure is not attached to the foundation by bolts or rebars, the foundation and the
superstructure are able to move independently minimizing the shock transfer to the walls. A rubble trench is also built of individual units rather than a continuous beam further absorbing the shock.

Earthbags are resilient. As per an experimental study on vibration reduction … Earthbags have a relatively high damping ratio with horizontal as well as well as vertical vibrations effectively reduced.

… All of these components make Earthbag structures extremely earthquake-resistant. Tests done in accordance with IBC standards have found that Earthbag construction far exceeds Zone 4 standards, devised to protect against the very highest level of seismic activity. Numerous Earthbag structures have been built in the United States. Earthbag structures are permitted by the California Building Code, the toughest in the United States due to high seismic activity.”

.

 

Categories
Construction Earthbags

Earthbag Cellar: Level 6 and 7 Done

After finishing level 6 we ordered another batch of sand (another 6 cubic meters, like the first batch).

20160912_105537

… and it was delivered just as we were getting started on Level 7 (because of tricky vehicle access to our property it came in two batches of 3 cubic meters) … this is the second batch being delivered with the first one in place:

20160912_120206

Layer 7 was relatively smooth sailing … that is with uninterrupted and continuous bag laying … also the overall wall length is shortening as both of the retaining walls are starting to shorten:

20160916_111547

This weekend I was alone and so could not progress with construction so I focused on preparing soil for the next two layers (I hope):

20160917_192657

We’ve pretty much used up the entire side-hill that was created during excavation. I pulled down 45 roughly sifted wheelbarrows of soil. You can see the soil pile that I’ve prepared behind the sand pile. That should allow us to make good progress with mixing and packing the next two layers. Its a tough job … and I hope I’ve seen the end of it .. at least for a while. After the next two layers we want to bring in the excavator to do some backfilling and to collect a large pile of soil next to the sand-pile … that should take us nearly to the end of the earthbag phase of this project

20160917_192517

We’ve had a fairly long stretch of work without rain interruption … but that is about to change. I’ve pulled the¬† plastic that will cover the walls, over the walls … and later today will go out and layout more tarps to keep the site as dry as possible.

20160917_192531

Categories
Construction Earthbags

Earthbag Cellar: Level 5 Done ready for 6