compressed earth block testing

Step by step process to make test bricks with different stabilisation percentages in batches of three.

1. Break up large amount of reasonably dry soil in cement mixer.
2. Put in container (eg wheelbarrow or makeshift bucket of tarp over 4 hay bales).
3. Fill brick press 1 litre at a time and take note of volume.
4. Press block with no stabilisation. Wait 5 minutes then move very carefully so as not to damage block.
5. Repeat steps 3 and 4 twice so there are three bricks with no stabilisation.
6. Take note of any height variance
7. Calculate the average volume of the material for an unpressed brick (upbV) and also 2.5%, 5%, 7.5% and 10% of said volume.
8. Making sure the cement mixer is completely empty, measure in 3 times the average volume of clay minus 2.5% (for stabiliser)
9. Add 3 times 2.5% upbV of cement and mix thoroughly (15-20 minutes). Add a light spray of water if necessary.
10. Transfer to block press and press block, taking the same precautions as with the previous blocks.
11. Repeat this process until there are 3 bricks with 2.5% cement, 3 with 5% cement and 3 with 7.5% cement and 3 with 10% cement.
12. Cover blocks in plastic for 2 days.
13. Lightly water the blocks every second day for 1 month to cure them.