Many variants on brick have been tried. Making bricks with tighter dimensional tolerances so they can be epoxied tightly together rather than using mortar is one approach. The mortar is usually the weak point. But it didn't "look like brick". There are cement bricks, and, of course, cinder blocks. There are "poured stone" blocks, mostly for decorative walkways. There are rammed earth blocks. There are bricks in nonstandard shapes.
Bricks are reused all the time, mostly in places with old brick buildings and an underclass of cheap labor to chip off the mortar. Like Chicago.
The "let's just dump random construction debris in" approach seems kind of iffy. Figuring out how to make something from broken concrete might be more useful. If you want some broken concrete, and are in Silicon Valley, there's a plant on Seaport Boulevard in Redwood City that gives it away. They charge to dispose of concrete, break it into small pieces, and give it away as "base rock". From the size of the pile they have, even giving it away is tough.
One of the secrets of making predictable handmade pottery is to grind up old pots and mix the powder into the clay. Since it’s already fired, it is size stable, which increases the stability of the material.
I don’t see why you couldn’t do the same with any other other wet materials, assuming you can fuse the new and old material properly.
Rammed earth is my favorite conceptually, especially if your property has the source raw materials on the property. You're not externalizing the impact of your build, and it deteriorates right back where it came from.
Yes, with the decline of coal as a fuel, the supply of cinders is much diminished. Also fly ash, which is what the electrostatic precipitators at coal fired power plants pull out of the exhaust gases. Fly ash can be used in place of sand in cement.
Key Benefits:
Largest recycled content of any building product on the market - over 90% recycled construction waste
These unfired units have excellent sustainability credentials - no gas use for firing, or cement required
Provides a market for recycled aggregates (gravel and sand) from construction and demolition sector
Significantly lower life cycle environmental impacts compared with traditional clay fired bricks/ cement-based products
In short - Easy recyclability, low resource use in manufacturing and low energy curing
Applications:
Creates a new product from waste that would otherwise be landfilled
Sustainable construction product suitable for internal and external load-bearing and “facing” applications
Lower cost recycled materials than in traditional bricks / cement-based products as well as reduced production cost per unit
Another alternative is bricks made from cork. The main use of cork is making wine bottle stoppers, which results in lots of left over material. Cork is more ecological than wood, as it's the stripped bark of the tree (the tree will continue growing once harvested and can be harvested multiple times).
In this process they grind up left over material from wine bottle stoppers, and heat it to form large bricks (it binds itself). The bricks are then cut on a CNC machine to give the correct form, and the waste material is sent back to the beginning of the process. Cork is a natural insulator, so building a house is more like stacking LEGO in this process.
I like hempcrete or hemp lime which is a mixture of hemp hurds with lime and sand. It's poured in place or made into bricks. However, the bricks also need cement for structural integrity, so it's best to pour it in place. One needs wooden framing to sustain the walls. I don't think it's scalable to build tall buildings using it but for regular houses it's perfect because it also has good insulation, vapour and thermal buffering characteristics.
We probably need something with enough structural integrity to be able to at least 3D print houses. The architects can then create a 3D model which is fed to a printing crane and printed in place.
I'm really enthousiastic for cross-laminated timber (CLT), which has such good properties it can even replace concrete skeleton in high-rise (10+ storeys) building construction. Plus applying it is a means to do carbon capture.
No details on the bonding agent used for binding the construction rubble.
But I really wish the world comes up with alternate building materials.
Currently, Cement has a large footprint. Sand used as filler, at-least in India, is in severe shortage and rivers are destroyed trying to mine it. And brick kilns consume a lot of energy.
Another non-fire eco-brick. These things have potential, but construction is a conservative business, especially when trying to usurp materials with proven performance history. But very few things with bricks is built to last 100+ years anymore, let alone 1,000. We're better off with a material that cost 1/10 the energy and last 1/10 as long than spending 10/10 energy on traditional manufacturing process for things that will last 1/10 as long anyway.
These guys have been doing something similar for at least a decade (I have no financial interest etc.): http://www.timbercrete.com.au
Also, I live in West Sussex and the amount of clay here really is unbelievable - my town used to be a major producer of clay and bricks, tiles etc. Once you're past a foot or so of topsoil it's pure clay.
To make it, construction and demolition waste including bricks, gravel, sand and plasterboard is crushed and mixed with water and a binder. The bricks are then pressed in customized molds. Tinted with recycled pigments, they can be made in any color
Is the binder cement? If so, then I believe those are called cinder blocks.
Bricks are reused all the time, mostly in places with old brick buildings and an underclass of cheap labor to chip off the mortar. Like Chicago.
The "let's just dump random construction debris in" approach seems kind of iffy. Figuring out how to make something from broken concrete might be more useful. If you want some broken concrete, and are in Silicon Valley, there's a plant on Seaport Boulevard in Redwood City that gives it away. They charge to dispose of concrete, break it into small pieces, and give it away as "base rock". From the size of the pile they have, even giving it away is tough.