UHPC Ultra High Performance Custom Cements
Vicon will design custom mixtures for exact specification parameters using diverse cement types, the correct fibers, in the correct dosages and precision casting methods to control water and air permeability as well as ductility and fracture energy.
Compared to advanced infrastructure steel/concrete solutions, used in the past 20 years and still within some current specifications; Vicon custom UHPC Cements provide:
• A 35% saving in raw materials • A 46% saving in primary energy • A 53% saving in CO2 emissions
ACI-239 Specification of UHPC is one of the elements clients ask us about. 22ksi is the specification, and this needs to be an average strength so 24ksi strengths should be in your testing to average 22ksi (about 95% of the time)
An Alternative can be: 20 to 21 ksi can be achieved with regular cement types IF proper mix design, admixtures and mixing apparatus is used with trained personnel.
We need a clear understanding of the exact strength needs: does the piece actually require these extra 2 ksi and will the price justify the increase in strength? EXACT permeability specifications for the function of the piece is required as well. Our specialists will assist with the nano engineering of Strength VS Cost VS Attrubutes so that oyur dollar per cubic yard is best utilized.
Vicon Nano Science improves the functionality of concrete. We create solutions within the fields of biomimetic, nanostructured and hierarchical materials which can be combined with fiber-reinforced concrete technologies in order to obtain ultra-high performance concrete UHPC with controllable stress-strain behavior. Vicon launched an avant-garde approach aiming to identify the nano scale phenomena underlying the behavior of concrete.
Our platform serves as a solid foundation for the development of new types of concrete, composed of ultra-high durability, manufactured with increased volumes of by-products, and self-healing materials. In addition, concrete with higher by-product volumes will provide greener economic solutions for the next generation of eco-concrete.
Reducing portland cement content by 50% or more and improving the overall performance of eco-concrete helps to reduce the carbon footprint of structures by 40-65% and, in addition, decrease the use of raw materials required for cement and concrete manufacture.
Thanks to a greater understanding of the material, it is now possible to produced better-structured concrete, with considerably improved properties compared with those obtained twenty years ago, making it possible to construct even more sustainable buildings and infrastructure.
For example, it is possible to manufacture ultra-high performance concrete, at a fraction of the price of current offerings. The Vicon cements are more durable and more resistant, allowing previously unheard of structural applications, using self-compacting concretes, which are more esthetic and easier to use on worksites.
Superhydrophobic concrete will establish the top sustainability benchmark and serve as the next technological platform for sustainable development of the concrete industry. Based on this platform, cement content can be reduced by at least 50% and the service life of developed concrete can be radically extended by a factor of 5+, a novel design paradigm for engineering cement-based materials with smart properties, providing the impetus for changing the way engineers design and construct concrete infrastructure.
Fiber additions to High Performance Cast Concrete Units:
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Using fiber is not for improving the compressive strength (and often reduces the compressive strength). Commonly, you will not see improvement of flexural or tensile strength as these are controlled by concrete cracking.
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Good improvement can be achieved with "strain-hardening composites" which are realized only with few fiber types: steel, shape memory alloys, PVA, and HDPE. The last 3 are expensive and actually, HDPE is very expensive (but works amazingly well).
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Fibers control crack opening, ductility and fracture energy.
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Fibers also will help to keep the tightness and reduce water and air permeability.
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The cost of a cement matrix to be used with fiber additions is doubled at least, and fiber prices differ widely, for example: (say for PVA this can be $400 per yd3/m3).
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Fibers can add to performance, but will the cost justify the performance? This ratio must be calculated for industrial scale manufacturing profitability factors.
If it is possible to manufacture “made-to-measure” concrete today, this is because of research
carried out over recent years. Vicon launched an avant-garde approach aiming to identify
the phenomena underlying the behavior of UHPC.
All this has been made possible by techniques or instruments: nuclear magnetic resonance, scanning or transmission electron microscopy, atomic force microscopy nanoindentation, synchrotron radiation, etc. All these tools have helped to reveal the highly technical nature of concrete in many respects (physical and chemical phenomena, sensitivity to external parameters, changes in mechanisms over time, etc.) and to develop knowledge of the mechanisms of concrete’s behavior on a nanometric scale.
Dr Sobolev is in the forefront of this science and “Custom Concrete” is what we provide our clients.
For further questions, please contact Melody Brenna melody@viconcement.com +1(806) 674-6072