Compressed Earth Block Test 

10% cement will allow a less precise mix, but it is expensive compared to other options. Start with 70-30, sand-clay, compressed, and less cement, 5%. Or, no cement and use emulsified asphalt throughout the mix, or, soak the outside of the block in it. Also, lime/flyash will act as cement. Or, half Portland, half flyash, saving a little on expensive Portland.

This is a great argument for sealing and painting the ENTIRE exterior of CEBS. I would also recommend to add a fresh coat of paint every 8 to 10 years, depending on your environment. FYI, I would also recommend sealing and painting the interior. Like with any structure, scheduled preventive maintenance will add decades to your home or building.

I have studied this for a while and my first thought was poor compression, possibly an inferior compression machine. This is not a new technology, there are structures in the world that been around for hundreds of years that show less degradation than your 10% portland blocks. I also noticed that none of your blocks contained any form of binder.

If you're adding 10% cement what's even the point? At 14% cement content you can make and pour concrete without any of the hassle of compressing the bricks.

Really missed out on "the proof is in this pudding"

If you followed the guidelines you would know that pure compressed earth blocks need 28 days to set. Convenient that you failed to mention that, nor the PSI that you compressed the earth block.

I'm researching on energy efficient affordable building blocks for low income homes. Your video just helped me see firsthand what will happen with 0% Portland. Being in a tropical climate, with all year round rainfall.... it will be a disaster! Thanks a lot for your video!!!

That's a good test but my guess is the cement will become brittle over time and the blocks will crumble. Earth bricks have been used worldwide for centuries and none of the oldest buildings have cement in the bricks. This test is relevant for flood prone areas, in which case you probably shouldn't build with dirt. Stabilized bricks are good for the first few courses in case the floor floods. I suspect cement laced earthen blocks don't perform their water wicking duties as well as clay blocks either because once cement gets wet it doesn't dry out. That is a collapse waiting to happen. Clay breathes, cement doesn't. Just a thought.

What about 15%?

Is "portland" regular building cement?

After all of the research I've done, the amount of bubbles, the unstabilized brick turning into mud, and the uneven compression of the 5% brick all tells me that your

Cool Video. But Portland is not the only thing with an impact to brick quality. Soil and aggregate properties, Sieves size, soil grading, clay content, granulometric form, mix proportions, pressure, stacking & Curing. Tthere are a lot of different influences to CSEB Quality. With the same amount of concrete (8% optimum) you can get very poor bricks (<1N/mm²) to extremely strong bricks (7-10N/mm²), always depending of the mixture AND Curing.

Excellent video! I am startingto make compressed earth blocks and I am going to test them as you described. I live on a ranch and I plan on building severalthings with compressed earth blocks.

You are a good guy,keep doing this n keep impacting me n millions all over the world especially Africa

That was a really fair test you did...ive often used the water plus subsoil or soil in a jar to work out good ratios for agronomy.Ive also worked with some guys in Australia doing rammed earth,and the lowest concentrate of portland they used was 6% up to 10%....and that depended upon the soil type in use,the climate,and the proportions of each...sand ,fine gravel,clay.The basic proportions were 30% of each,with that 10% variable,preferably towards the clay or gravel...so an ideal 30% sand,35% clay,35% gravel.Ironstone soil tended to be the most readily available ideal proportions,basalt tended to need fine gravel,granite tended to need clay.....etc

Good information. thank you.

Wow!!!! Thank you so much.i just subscribed to your channel

Wow ,this IS very informative, thank You so much for ur video

May have missed this but do you have a video addressing the challenges with local building authorities?

This is a great video. I was thinking of maybe granite stones for the first 1 meter of the wall, followed by compressed rocks for the rest of the structure if that could work?