For Comparison purposes, below are some bullet points of the currently available construction resins widely used in additive manufacturing:
- Produces sturdy, shatter-resistant parts
- Ideal for functional prototypes and mechanical assemblies
- Has excellent resistance to cyclic loads
- Not suited for thin walls (1 mm is the recommended minimum)
- Harder to remove from the build platform than standard resins
- May cost up to $300/kg $136/lb
- Produces fragile parts with low impact resistance
- Ideal for detailed and high-resolution prints
- Produces smooth surface finishes
- Affected by color (like smooth/shiny finishes)
- Relatively easy to use
- Low cost
Dimensional Bonded Fillers as a composite material resin are developed for applications that can withstand high strain and stress. Mechanical properties of cured articles produced from these geopolymer resins can not only rival the highest grade organic industry grade plastics, but exceed them when it comes to sustainability and reducing atmospheric carbon dioxide emissions.
Introducing GeoChem™ a Water Based Resin Systems
GeoChem resins are under development for applications requiring materials that can withstand high strain and stress. In fact, the mechanical properties of the cured parts produced have concrete like properties that rival industry-grade plastics without the environmental burden of carbon dioxide.
Balancing strength and code compliance, GeoChem resin is a great choice for sustainable, functional transportation road pavements and bridge assemblies that need to undergo short periods of high mechanical stress. This makes GeoChem systems ideal for asphalt and concrete infrastructure repair and use in other objects that need to withstand abrasive wear and tear.
Such ultra-high-performance resins with cured ductile ceramic like properties can pose their own challenges when compared to standard resins. Some may require professional 3D printers, and or controlled atmosphere casting, and most are simply well above the budget for most down to earth projects. For the uninitiated in material engineering without unlimited budgets like government aerospace and defense contractors a group of small business California artisans came up with some ideas to develop and upcycle past mineral mining fields and urban landfill into energy efficient products of today with life-cycle costing when compared, makes good on the old adage when time is money “ If you haven’t enough money to do it right the first time; where are you going to find the money to do it twice?”
Introducing SILICONITE™ a natural mineral hybrid polymer low embodied energy catalyst
- Produces stone- like cast or molded parts with high impact resilience
- Ideal for subgrade soils stabilization and waterproofing
- Has long range dynamic mechanical properties
- Suitable for thin film coatings on substrates
- Can be foamed for high dielectric applications
- Cast pervious nano membranes to ductile metallic like sheets possible
Principal Investigator Paul F. Pugh believes 3D printing and additive continuous casting manufacturing opened up the green door of opportunity in construction for boosting both energy efficiency and conservation creativity.
“3D concrete printing technology as a facet of robotic computer aided shotcrete has real potential to revolutionize the construction industry, and our aim is to bring that transformation closer,” said Pugh, a former California General Engineering Contractor with a specialty in dielectric materials manufacturing and experience handling high efficiency [low loss] electrical energy insulated conductor infrastructure systems.
“Our study explored how different nano sheet aluminosilicate patterns affected the reformed structural integrity of plastic clay soils, and for the first time revealed the scientific benefit of a bio-inspired clean approach in inorganic mineral bonds [referred to as covalent bonds].
“We know that natural materials like Scorpion exoskeletons have evolved into high-performance structures over millions of years, so by mimicking their key advantages we can follow where nature has already innovated.”
3D printing for construction
The automation of concrete sheet panel construction is set to transform how we build, with construction tools, materials, and Green methods that will soon be known as the next frontier in the automation and digital data-driven revolution known as Industry 4.0.
A 3D shot-Crete dispenser builds houses or makes structural components or feeds a pavement screed by depositing the material layer-by-layer, unlike the traditional approach of casting concrete in a mold. This novel equipment utilizes the concept of volumetric mixing and dispensing insitu [onsite].
With the latest technology, a house exoskeleton can be 3D printed in just 24 hours for allegedly half the cost of a stick build wall, ceiling and roof weather resistant shell. Promoters of the craft claim the world’s first 3D printed community began in 2019 in Mexico.
The emerging industry is already supporting architectural and engineering innovation, such as a 3D printed office building in Dubai, a nature-mimicking concrete bridge in Madrid and The Netherlands’ sail-shaped “Europe Building, and a hotel in the Philippines “
Our research team out of Terra Bella/Porterville/Springville, California focuses on soil cements, exploring ways to enhance the clay subgrade of inferior soils in agriculture zones using different mineral and water combinations to stabilize these soils and render them suitable for such diverse applications from rapid plant growth to handling truck traffic on all weather roads with fewer potholes made possible using nano- pattern design, geopolymer powders, modelling, design optimization and reinforcement options.
Patterns for printing
The most conventional pattern used in 3D printing is unidirectional, where layers are laid down on top of each other in parallel lines [similar to lifts in asphalt pavement].
An unpublished study by our team was based on using Additive Manufacturing for improving sustainable pavements and infrastructure repair. We investigated the effect of different nano-sheet silicate mineral patterns and the impact that they might contribute to dynamic strength when reinforced [copolymerized] with landfill diverted upcycled synthetic carpet fibers to enhance concrete ductility and promote lower temperature asphalt pavement mix designs. [available on request]
Previous research by ACI [American Concrete Institute] found that including 1-2% short polyester fibers in an ordinary concrete mix reduces defects and porosity, increasing strength. The fibers also help the concrete harden sooner without deformation shrinkage, on hot days and mass pours.
Complex Duplicatable Structures since 2016
Other findings showed strength improvement from each of several mixes, with up to 75% less ordinary cement in the mix yet exceeding specified compressive strength by 2x, indicating promise for low density and foamed composites able to support a range of dynamic mechanical loading.
“This work is in early stages, so we need further research to test how the concrete performs under a wider range of parameters, but our initial experimental results show we are on the right track.”
Further studies will be supported through a new large-scale mobile concrete precast block plant to research Nevada and Southern California pozzolan deposits for possible franchise sites to support the commission of planned development communities housed with this innovative energy saving building material alternative to wood, gypsum plaster and asphalt shingle roofing.
The robotic casting software will be used by the team to track the best economic method to research the 3D printing of houses, buildings and large structural components under California’s mandate for solar powered roofs and geothermal heating and cooling.
The team also hopes to prototype the new additive manufacturing machine to explore the potential for 3D printing with concrete made with recycled waste materials such as light weight plastic aggregate as well as agricultural waste and contaminated soils.
There exist a large number of untapped California industrial mineral sources rich in alumina and silicon with the potential for procuring geopolymers. Among the dominate sources are clay soils, pozzolans, kaolins, illite/smectite, decomposed granites, pumicites and rhyolites. Geopolymers result from the reaction of aluminosilicates in fine powder form with an alkaline silicate solution.
Industry 4.0 finished goods made from the geopolymer process display several high value properties:
- use in thermal insulation,
- thermal shock refractories,
- production of low energy ceramic tiles,/blocks/wafer panels
- cements and concretes,
- high-tech fire proof composites for aircraft and automobiles interiors,
- high-tech resin systems,
- in radioactive and toxic waste containment,
- in fireproof fuel cell housings and battery containment devices
- low cost carbon negative housing
Geopolymer mix designs are generally known to have high compressive strength, fire and acid attack resistance, low water absorption and thermal conductivity. Our team surveyed over 10,000 acres of California rangeland as sources for different materials suitable for procurement to complement the geopolymer industry. We reviewed geopolymer press releases and found a trend that suggests when compared to ordinary California Portland cement as a building material that when synthesized geopolymers display compressive strength and water absorption resistance that easily outperform OCPC. [ordinary California Portland Cement] The findings of one of our study’s indicated that compressive strength of a California geopolymer mix increases with increase in concentration of sodium silicate as well as sodium hydroxide. Water absorptivity of a local geopolymer decreased with an increase concentration of sodium hydroxide, water glass or Siliconite™ and the duration of the geopolymer curing time also decreased.
Versatility of geopolymer can be measured from civil applications in term of high compressive strength for geopolymer cement and concrete, acid attack resistance, quick repair of materials for ancient archeological structures, to the interior of modern aircraft which make use of fire-resistant properties of geopolymer composites. Due to the fact that geopolymer composites did not ignite, burn, or release any smoke even after extended heat flux, they are suitable as electric automobile cabin materials for cargo liners, ceiling, floor panels, partitions and sidewalls, stowage bins, sound dampers and wire insulation.
Most North America scientific and industrial disciplines, such as modern inorganic chemistry, physical chemistry, mineralogy, geology, analytical chemistry and all types of engineering process technologies, should be encouraged under 4.0 Green manufacturing standards to exploit the versatility of the geopolymer process.
Other potential applications for geopolymers include:
- decorative stone artifacts,
- thermal insulation,
- soil-tech building materials,
- low energy ceramic tiles,
- refractory items,
- thermal shock refractories,
- foundry applications,
- cements and concretes,
- composites for infrastructures repair and strengthening,
- high-tech composites for aircraft and automobile interiors,
- high-tech resin systems,
- radioactive and toxic waste containment,
- arts and decoration,
- cultural heritage,
- archaeological site preservation and protective coatings
It was also discovered that manufacturing of geopolymer composites, unlike Portland cement can rely on only clean renewable energy sources. Further, the use of waste products like fly ash, blast furnace slag etc for manufacture of geopolymers has led to tremendous potential for geopolymer use not only sequestering hazardous waste encapsulation, but also through upcycling with geopolymer this technology can convert many landfill waste streams into a useful product.
Emission of CO2 from cement production is increasing at a much more rapid rate than all other industrial sources put together. Manufacture of Portland cement generates CO2 through calcination of raw materials and fuel consumption. It has been indicated through industry records that 1 ton of Portland cement generates 1 ton of CO2. It has also been concluded from review of carbon cap and records that with demographic growth and industrialization, the pollution generated by Portland cement production in a few years will represent 17% of worldwide CO2 emissions (currently it is around 8%). By the year 2025, global CO2 emission from the manufacture of Portland cement will exceed 3,500 million tons annually. Manufacturing geopolymeric cement generates at least five (5) times less CO2 than does the manufacture of California Portland cement. By California and Nevada Portland Cement Plants converting to the manufacture of geopolymeric cement/concrete would eliminate 90% of the emissions generated from the mined construction material industries in these two states. California local sourced geopolymer manufacturing features a 90% or greater reduction in carbon dioxide emission without losing any jobs.
Story Source: Materials provided by Rio Blanco Development in joint cooperation with Sequoia Valley Testing and Inspections, a private DBE, California Department of Transportation registered and calibrated soils and concrete materials testing laboratory. The managing consultant and geotechnical mineral advisor is a graduate of the Mackay School of Earth Sciences and Engineering/ founder of Quaternary Technical Solutions, a California LLC.