Clay/Aggregate Ratio of Soil

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Today I'm demonstrating how you can adjust the clay/aggregate ratio of your soil that goes in the earthbags. This mixture of road base is very good, but maybe it can be improved by a small percentage of additional clay. So I'm going to add 5% extra clay and make a test earthbag, and then we'll check the results later after it dries.

Make sure to mix it thoroughly. Here's what we have so far. I mixed a little bit of clay with one bucket of road base and it's looking better. The point of this is to make sure you have enough clay to 'glue' the sand and gravel together and make it nice and strong. We're tamping the contents after we add each bucket of soil to make sure it's well compacted. Add the same amount of clay to each bucketful. I can see a visible improvement, there's a pretty good difference in the amount of clay. I think this will be stronger. Looking in the bag, it looks like a more solid mix, so I think this test will prove successful. I'm going to put the earthbag against the wall before I tamp it to simulate an earthbag in the wall -- see? That way it won't expand too much. You can see a little clay coming through the bag. There's just a little bit too much water, but it looks good so far. We're going to dry it about two weeks and then remove the bag.