Poured Earth

The poured earth technique is an innovative building technique, using earth in a plastic state. Our ongoing research project aims to discover and master this technique so it can be shared and used in our future building projects. If mastered, this technique would reduce consequently the building time and would be an easier way of building with earth compared to compressed earth blocks or rammed earth.

How it works:

We seek to be able to pour earth just like concrete, thus to have the same workability.
In order to reach a good workability, earth concrete must be very plastic. But adding too much water would weaken the structure and result in shrinkage and cracks when drying.
So the main issue is to liquefy earth without adding too much water.

Since the beginning of the project in January 2011, we are designing and performing tests, looking for the right admixtures and additives, juggling with proportions and quantities.

For the moment we are experimenting with a variety of additives such as washing powder, ashes, soapnut, or classic concrete plasticizers.

The tests:

We are performing three kinds of tests during our experiments. A linear shrinkage test that estimates the shrinkage ratio of a specific mix, the shrinkage must be very little to avoid cracks in the structure. A slump test that allows us to approximate the workability of an earth concrete, it must be plastic enough to be handle like concrete. And a compressive strength test which testifies the resistance of the material and its ability to take the load of a building, which is the most important property of a building material.

Linear shrinkage test
Slump test
Compressive strength test