Watershed Materials - Technology for New Concrete Blocks
The block with a smaller carbon footprint.

Blog - Watershed Materials - Watershed Block

Blog updates by Watershed Materials. Developments for sustainable new concrete block technology funded by the National Science Foundation.

More Compression and a Faster Machine - Big Steps Forward For A New Age of Masonry

High power in a small package. What sets the Watershed Materials block machine apart from the others is the Archimedean principle of compound force. “Give me a long enough lever and a place to stand and I could move the earth.” And it's not just brute force that squeezes grains into stone but smart force. Eight 4:1 lever arms multiply the compression energy of four four inch hydraulic rams working on two heavy steel platens, all teaming up to deliver 250 tons of force into each block.

Watershed Materials has been sequestered in our research lab working on improvements to our prototype machine for making high performance concrete block with less (or zero) cement. We’re proud to share our progress towards a market ready platform for masonry block manufacture using a much wider array of locally sourced, unwashed, often recycled aggregate and using far less cement - even zero cement with our newest lime / slag and geopolymer mix designs.

The newest iteration of our high compression prototype masonry block manufacturing equipment has increased the total applied compressive force to 500,000 pounds - yes, that’s half a million - and has been equipped with computer controls and improved hydraulics for faster production. The intense compressive force that this new block machine applies in the manufacturing process is critical to achieving Watershed Materials’ two guiding principles - reducing cement in structural masonry and utilizing locally sourced, minimally processed natural aggregates. 

Our new machine is able to reduce - or eliminate - cement by compacting aggregates with such force that the mineral grains are lithified into a kind of man-made stone, mimicking the natural forces that create rock deep in the earth under intense geologic pressure. The difference between our machinery and the earth’s is that what takes eons in nature can be expressed in seconds on the factory floor, especially with computer controls.

One of the tricky parts of making any block is getting it out of the mold without breaking. High compression and clay in the formula help the newborn blocks to stand up on their own but that doesn't mean they're not fragile. The same thick steel plates that form the sides of the mold carry the fresh blocks out of the compression chamber and set them gently onto the offloading conveyor where they quickly gain more strength. 

Traditional concrete block isn’t made with any significant compressive force in the manufacturing process because concrete block achieve all their strength from cement. Which would be fine if cement weren’t the notorious polluter that it is, responsible for a whopping 6% of all of humanity’s greenhouse gas emissions. Watershed Materials has invented a new, smarter way to manufacture concrete block that doesn’t just rely on cement to glue rock together but rather re-structures aggregate into a dense matrix that produces durable and beautiful structural masonry block.

Some of Watershed Materials’ mix designs still use cement, but at a significantly reduced level - up to half the cement of traditional concrete block. Other more advanced mix designs eliminate cement altogether by utilizing alternative binder formulations including lime, slag and aluminosilicate as well as natural clay geopolymers. All these mix designs require and take advantage of the ultra high compression provided by this new block machine.

The second big way that compression is key to the Watershed Materials’ masonry manufacture process is that compression takes advantage of the natural grains present in aggregate - minerals that are traditionally washed out of the aggregate used in concrete. Traditional concrete - and concrete block - rely on cement for stabilization, and the minerals and rock dust naturally present in aggregate interfere with cement’s stabilization process, so those minerals are washed clean of the virgin mined aggregate. Watershed Material’s process, however, takes advantage of these minerals and rock dust in the high compression manufacturing process. We can use a much wider range of locally sourced, often repurposed or recycled aggregate rather than the dull grey washed virgin mined aggregate used in concrete, saving a lot of water and repurposing existing material.

To raise eyebrows in the deeply entrenched world of concrete masonry we knew it wasnt enough that our new block machine produced beautiful, sustainable block with less cement. It had to be FAST. Solenoid valves and a programmable digital logic controller speed up cycle time.

Beyond increasing the compression used in the manufacturing process, the Watershed Materials team is working to speed the production cycle time so that more block can be made in each production shift, increasing output and reducing cost-per-unit. We’ve added faster hydraulics and a computer control network sending signals through six solenoid operated valves. If all goes as planned, anticipated cycle time will be fifteen seconds, resulting in a production output of over 1,500 block per shift- all with mostly automated, computer controlled systems.

Watershed Materials envisions three real-world scenarios for applying the technology: large scale, permanent high output factory applications like those traditionally used in the manufacture of concrete block; temporary on-site “pop-up” manufacture of block using on-site aggregate from off-haul, excavation and demolition on large job sites; and smaller, distributed hyper-local manufacture of block for disaster relief and other housing needs in remote areas where cement is imported and expensive.

Programmable logic controllers are used to run things like sorting machines at Amazon and giant earthmoving equipment for construction sites. They eliminate guess work, increase efficiency, and reduce errors. They can tell you that a part is going to need to be replaced before it does.

Next up is a four month testing regimen where the new high compression block manufacturing platform is tested over repeated 7 hour production shifts, highlighting further room for improvement. Stay tuned for the next release of updates - we’re on a quest to develop technology for making high performance masonry using as little cement as possible and taking advantage of the beautiful, natural aggregates found locally all around the world.