Cor-Tuf® UHPC Partners
83 Victoria Street
Product Development OfficeSuite 500 3455 Peachtree Road NE Atlanta, GA 30326 USA
Project Engineering Office
S-302, Greater Kailash-11
New Delhi 110048 INDIA
Cor-Tuf UHPC: Get the Benefits of UHPC Along with the Production Methods of Traditional Concrete
Our proprietary Cor-Tuf UHPC mix is the only one on the market that can be mass produced, mixed, and poured using conventional concrete machinery.
Despite the exceptional strength, durability, and flexibility of Cor-Tuf UHPC, it is still concrete. The mix can be poured using a variety of industry-standard means and methods, including ready mix trucks, Tuckerbilt dispensers, skid-steer auger buckets, and all types of conventional wheelbarrows, buckets, and buggies.
Cor-Tuf CT25 is our standard material formation. CT25 is a highly versatile mix that can be used as a direct replacement for standard concrete. It is compatible with all industry-standard production techniques, ranging from large-scale precast facilities down to small, cast-in-place applications. This includes (but is not limited to):
- Pre- and post-tensioned structure component construction
- Precast panels
- Field-cast structural connections
- Wear surface overlays
- Marine installations
- Injection and extrusion techniques
- Tilt-up construction
- Blast and corrosion resistance
- Cast-in-place joints
Cor-Tuf UHPC versus Traditional Concrete
Approximately 75-80 percent of the ingredients in Cor-Tuf UHPC are the same as regular concrete—cement, sand, and water. The remaining 20-25 percent of the ingredients are what make it unique. Integrated fibers made from materials such as polyester, fiberglass bars, basalt, and steel are added to the mix to create a progressively stronger end product. The addition of steel delivers the greatest gains in strength.
Here is a closer look at how Cor-Tuf UHPC compares to traditional concrete:
The advanced compressive strength of Cor-Tuf UHPC is particularly significant when compared to traditional concrete. While traditional concrete normally has a compressive strength ranging anywhere from 2,500 to 5,000 psi, Cor-Tuf UHPC can have a compressive strength of up to 10 times that of traditional concrete.
Cor-Tuf UHPC has a tensile strength of 1,653 psi, while traditional concrete typically measures between 300 and 700 psi.
Cor-Tuf UHPC can deliver more than 3,163 psi in flexural strength; traditional concrete normally has a flexural strength of 400 to 700 psi.
Here’s one of our H-beam pilings. This 30-foot beam was subjected to 84,000 psi of downward flexural pressure and 4.5” of deflection before failing, and when it did crack, its failure point was consolidated to one area with no additional radiating cracks along the sides of the piling. Outside of the drastic numerical difference between their capacities, the primary difference one would notice between the failure patterns of conventional concrete and Cor-Tuf UHP is that when conventional concrete fails it fails catastrophically. Typically the failure pattern of conventional concrete is explosive with considerable shrapnel debris likely. There will also be large radiating cracks from the failure point often compromising the element beyond the ability of repair.
Cor-Tuf UHPC has a higher density than traditional concrete, making it virtually impervious to water. The material does not deteriorate when exposed to deicing chemicals or sulfates. Studies have shown that Cor-Tuf UHPC can withstand more than 1,000 freeze/thaw cycles, making it highly superior to regular concrete.
Impervious to Water
Cor-Tuf UHPC is moisture-resistant due to its higher density. This makes it almost impossible for ordinary water to penetrate the surface.
Cor-Tuf UHPC is a saltwater-resistant concrete, making it ideal for use in bridges, seawalls, and other structures built in or near seawater.
Cor-Tuf UHPC does not deteriorate when exposed to deicing solutions or sulfates.
Cor-Tuf UHPC can absorb three times more energy than regular concrete. Under impact loading, Cor-Tuf UHPC was twice as strong as regular concrete and dispersed up to four times as much energy. This makes the material a great candidate for earthquake-resistant bridges and buildings.
Cor-Tuf UHPC can be stretched out into thinner sections under tensile stress, unlike regular concrete.
Longer Useful Life
Cor-Tuf UHPC lasts up to 100 years versus 15 to 25 years for traditional concrete.
Even though Cor-Tuf UHPC is stronger, less material is required, so the end structure is lighter in weight, which reduces footing and support requirements.
Better Than Steel
Cor-Tuf UHPC is unique in its ability to deliver the strength of steel at a lower life cycle cost. It delivers the same performance capabilities of steel, but with smaller components. Benefits include:
- Resistance to oxidation (will not rust or deteriorate); impermeable to air and water
- Resistance to environmental degradation (ideal for marshes and saltwater environments)
- Virtually limitless aesthetic potential (especially when compared to the fixed qualities of steel and how it weathers over time)
- A 100-year product lifespan, lowering the overall lifetime and maintenance cost of a project
Cor-Tuf UHPC delivers lower life cycle coast when compared to steel, thanks to:
- Faster project completion with prefabricated UHPC elements
- Reduced transportation and machinery costs due to less material requirements
- Reduced sizing and complexity of footing and support requirements
- Virtually no maintenance costs due to extended longevity, durability, and resistance to natural forces such as freeze/thaw cycles, storms, and water damage
Cor-Tuf UHPC delivers the same strength advantage of steel (at up to 50,000 psi), but it is less expensive than steel; is more stable in softer soils; requires less maintenance; is impervious to water, resists more than 1000 freeze/thaw cycles. Best of all, Cor-Tuf UHPC can be mixed, transported, mass-produced, and poured—just like regular concrete.
Low Impact Design
Cor-Tuf UHPC is the premier material for Low Impact Design (LID). Reduced emissions and ground disturbance make construction cleaner and greener. When you choose to work with Cor-Tuf UHPC, you can lower the total cumulative carbon footprint of your project through reduced transportation needs, decreased Limits of Disturbance (LOD), smaller machinery for installation and transport, and reduced maintenance requirements.
Defense and Security
Cor-Tuf UHPC was first developed by the U.S. Army Corps of Engineers to protect personnel and weapons facilities. The material’s superior compressive and tensile strength combined with its ductility and impact resistance result in a blast-resistant end product. Choose Cor-Tuf UHPC for protection from debris impact from natural disasters, blast-resistant panels and bank vaults, and armored protective enclosures.
Cor-Tuf UHPC Seawalls
Seawalls made of traditional concrete are not immune to the effects of seawater, and bridges constructed of regular concrete are proving to be incapable of withstanding the damaging winds and forces of hurricanes and other damaging storms. However, Cor-Tuf Ultra-High Performance Concrete (UHPC) is capable of withstanding hurricanes. This marine-grade concrete also doesn’t corrode or deteriorate in seawater, making it the best material to use in seawall design and construction.
Our seawall system uses Cor-Tuf UHPC H-pilings. We cast a large, solid sheet panel that slides between the two H-pilings, and a cap is placed on top. Given the exceptional tensile strength of Cor-Tuf UHPC H-pilings, our seawalls don’t require buried tie-backs. Since the wall is made entirely of Cor-Tuf UHPC, all of the usual benefits of superior strength, durability, and flexibility make these walls exceptional.
Why Cor-Tuf UHPC
Many conventional UHPC mixes are incredibly strong and durable, but present other challenges when it comes to usage and consistency. For example, most conventional UHPC products cannot be mixed, poured, or transported using standard concrete machinery. They cannot be mass-produced either, which creates unwanted down time on the site and can create inconsistencies in the end product.
There are several characteristics of Cor-Tuf UHPC that make it a better choice than other UHPC products on the market.
Mass Production Using Conventional Methods
Many conventional UHPC mixes cannot be mass-produced. In fact, many produce their UHPC in 50-pound bags, which quickly becomes an issue when working on large concrete structures. Cor-Tuf UHPC, however, is capable of mass production. We are using Super Sacks that hold approximately one ton of material when we produce a batch. We are also designing our batch plants to accommodate silo-style mixing and currently have a mobile batch plant in the works.
A 100-foot Cor-Tuf UHPC H-piling, seen here from the top, was subjected to pressure from a D36 and D62 hammer. Regardless of which hammer we used, or how forcefully or rapidly we attempted to hit the piling, our data showed that the structural integrity of the piling never dipped below 100 percent. This is what the piling looked like, from the top, afterwards. The only damage done was the minor discoloration left from where the hammer pad had caught fire; you can see remnants of the pad in this picture. Cor-Tuf UHPC can be used for any size or type of project.
Many conventional UHPC products are not flowable. That’s why many of them have not been used on large projects such as bridges and pilings. Cor-Tuf UHPC is different. It is flowable, pourable, and pumpable! So it can (and has) been used to make large structures. It pours the same as regular concrete, but you get all of the added benefits of strength, durability, and workability.
Small batches require constant measuring and mixing of ingredients to make sure you get the required strength and pourability of the final product. When this is being done in small 50-pound bags, the margin for error becomes quite large. Since Cor-Tuf UHPC is produced in large quantities, these consistency issues do not exist. You get a uniform mix every time, so you can be confident you’re getting the strength and quality you expect.
Conventional UHPC typically takes 20 minutes to mix. Combine this with the small batch process problem, and you end up with a lot of downtime on a job site. Pours are done in stages, a process which reduces quality and causes workers to sit idle waiting for the next batch to be ready. Cor-Tuf UHPC, however, mixes in about five minutes, and in much larger batches. Downtime on the site is virtually eliminated.
Many contractors and builders are hesitant to use a new product such as UHPC because they don’t want to change their familiar process or machinery. This is completely understandable. Your workforce is accustomed to a certain process and is well-versed in how to operate existing machinery efficiently and safely. While many conventional UHPC products cannot be mixed, poured, or transported with standard machinery, Cor-Tuf UHPC can.
Most conventional UHPC products have a working time of less than an hour. This creates logistical issues, especially when you’re dealing with small batches that take 20 minutes to mix. Cor-Tuf UHPC has a working time of well over an hour. Better yet, the product can be engineered to increase or decrease this time if needed for a given project. Jobs are thus more efficient with less strain on supply chain logistics.
Cor-Tuf UHPC can be engineered into a unique mix design to meet the needs of any project. Increases in strength come from the proprietary combination of integrated fibers worked into the mix. A variety of fibers can be used to achieve desired strength. If you need a self-leveling mix or if you need the concrete to stand up once poured, Cor-Tuf UHPC can be engineered to perform in either manner. We can also tailor the mix to increase or decrease the working time once poured. There are an infinite number of variations. You get the exact mix needed for any given job.
When dealing with a non-proprietary mix, there is no guarantee of what you get. Variances in the quality and mix can ruin a project. Cor-Tuf UHPC has strict quality control procedures in place; it is a company priority. We know how important consistency is in order to become the world’s most reliable UHPC provider. The product is only available through licensed dealers and distributors, each of whom are thoroughly educated on the product.