UHPC Manufacturers can be found worldwide. In the USA there are only a handful that have been tested and verified. One of the few is Steelike(R) UHPC Mix Design. It has taken over a decade of testing and was recently used in a FHWA Project. Contact us for any request or application you may have.
The challenge facing the UHPC industry is creating a mix design that can be consistent in it’s ability and testing. Multiple recipes are posted online. many of these state things such as “Cheap UHPC” or “UHPC made with local ingredients. This type of marketing most often yields a very strong concrete mix design but not a UHPC that can consistently perform as it relates to the multiple prerequisites involved. Yes, you can make a concrete with high compressive strength but that alone does not make UHPC. Like a porcelain plate, with impact it will shatter like glass.
So what is UHPC?
UHPC is a ultra-high performance concrete that is also very ductal in nature. it has been tested by the FHWA and multiple Departments of Transportation throughout the United States. The construction industry is beginning to embrace ultra-high performance concrete because of many reasons including it’s performance. It can reduce the mass required in multiple applications so although more expensive, less material can be used. Just one example of this would be UHPC panels and thin overlays but there are many more exciting uses being created.
According to the FHWA “UHPC is a cementitious composite material composed of an optimized gradation of granular constituents, a water-to-cementitious materials ratio less than 0.25, and a high percentage of discontinuous internal fiber reinforcement. The mechanical properties of UHPC include compressive strength greater than 21.7 kilopounds per square inch (ksi) (150 Megapascals (MPa)) and sustained postcracking tensile strength greater than 0.72 ksi (5 MPa). Ultra-high performance concrete has a discontinuous pore structure that reduces liquid ingress, significantly enhancing durability compared to conventional and high-performance concretes.”
Locally sourced materials?
This becomes somewhat blurred for obviously no one location will have the necessary raw materials and additives to create an authentic UHPC. Sand for an example. Being that sand averages over 50% of a UHPC mix design and is crucial to the particle packing required, it is hard to believe that a recipe that works in one state will be identical five states over. More so, if I create a mix in Chicago, have it tested and approved to be used in a bridge project, which takes months, can I then eliminate the required testing if I change the recipe due to using locally sourced sand in a different state.
The Difference between UHPC Manufactures and Locally Sourced Material
The biggest difference will be consistency. When UHPC is correctly blended, each tablespoon will be the same and be consistent from batch to batch, placement to placement and project to project. I’ve seen an unnamed UHPC batched on several different occasions and the water amount required to produce the same slump changed in multiple batches. So the advantage of using a UHPC Manufacturers capable of making the exact same mix design every time becomes well worth the additional cost. When using Steelike® UHPC Mix Design, you will never have to worry about the mix design changing based on the sand of the day approach nor have to add more or less water because of a locally sourced sand containing extra water any given day.