At Cor-Tuf, we are committed to continuing to push the boundaries of what concrete can do. For example, we recently introduced our 18”x18”x100’ Cor-Tuf Ultra-High Performance Concrete (UHPC) square piling to the market. Now we are able to report a new breakthrough: an H-piling that has the same performance as our square piling, but uses half the required material. This piling is the first mass-produced UHPC piling to be used in an American bridge project.
You may remember the outstanding results achieved in the tests conducted on the square piling, such as its ability to withstand 84,000 psi of downward flexural pressure and 4.5” of deflection. We were also able to drive the piling through 20’ of bedrock (90’ in total). The integrity of the piling never dipped below 100 percent, regardless of the size of the hammer we used to drive it.
Similar results with half the material
Cor-Tuf UHPC square pilings generated such great reviews that we received requests from several state Departments of Transportation to take our product one step further and create pre-tensioned Ultra-High Performance Concrete H-pilings. We were more than happy to continue the Cor-Tuf UHPC revolution and are thrilled to announce that the H-piling has arrived.
Our team has just completed a series of tests on the new H-pilings. We are proud to report that this new concrete product exhibits the same abilities to withstand extreme compressive and flexural loads as our square pilings—all while using approximately half of the required material to produce it. The net result of this material savings is a lighter weight, more cost-effective end product that has the potential for further savings over the lifespan of a project when additional factors such as transportation and installation costs are considered.
Cor-Tuf UHPC H-piling
Overall cost savings with Cor-Tuf H-pilings
One of the main benefits of Cor-Tuf UHPC H-pilings is the reduction in materials needed to produce it. We achieved this by not including additional supporting steel stirrups within the product outside of approximately 4’ of either end. This is quite a difference from our square pilings, which have stirrups throughout the entire length.
The stirrups form a supporting cage around the pre-tensioned steel cables that are embedded within the piling. The H-piling does away with nearly all of the stirrup steel used for the cage and cuts out roughly half of the cementitious requirements of the square piling to create a product that is roughly 20 to 30 percent lighter. This can result in a huge critical path savings for a large-scale construction project when material freight and piling placement are factored in.
You may be wondering how this product is able to perform at this level with so much less material. The answer gets to the heart of what makes Cor-Tuf UHPC so revolutionary. Unlike traditional concrete, Cor-Tuf UHPC exhibits a highly balanced ratio of extreme compressive and tensile strengths without sacrificing its ability to remain flexible. This flexibility allows the material to absorb and distribute the force of a blow throughout its entire form.
Stirrups and supporting cage around the pre-tensioned steel cable
Using Cor-Tuf UHPC H-pilings on your next construction projects delivers efficiencies throughout the project lifecycle, making the entire critical path more efficient. The benefits of Cor-Tuf UHPC H-pilings include:
Lighter weight—Cor-Tuf UHPC H-pilings use half of the materials required for our square pilings, creating a 20 to 30 percent lighter product that is easier to transport to and from work sites and easier for your crew to install.
Less expensive—Less material directly translates into a lower cost, making UHPC pilings a realistic option for more construction projects.
Increased truck capacity—The lighter weight of our UHPC H-pilings means trucks transporting pilings to the job site can carry more pilings in each load.
Lower transportation costs—The ability to carry a greater number of H-pilings per truck reduces the number of trucks and trips needed for a job, saving substantial money on transportation costs.
Perhaps the best part about our UHPC H-pilings is that they deliver these benefits without any sacrifice in performance. You get the same strength and durability as you do with our square pilings. Simply put, they just don’t break. Your construction team can focus their time and energy on installing the pilings rather than fixing (or replacing) ones that are damaged or broken, as so often happens with traditional concrete pilings.
The results are in: Cor-Tuf UHPC H-pilings outperform traditional square pilings
When we decided to test our new Cor-Tuf UHPC H-pilings, we didn’t hold back. We actually conducted our tests in a swamp environment, truly putting the integrity, strength, and durability of our product to the ultimate test.
As in our previous tests, we used our one-yard super sacks of premixed dry constituents to manufacture the piling with a top-down, gravity-fed production methodology, demonstrating the ability to mass produce concrete structures with Cor-Tuf UHPC. Once complete, the H-piling was free of any cold joints, voids, bug holes, and scaling.
The H-piling was tested in conjunction with the Florida Department of Transportation as part of a project to widen and replace a two-lane bridge. The Florida DoT wanted to compare the installation of our Cor-Tuf UHPC H-piling with square pilings made from traditional concrete. As we mentioned, this was the first mass-produced UHPC piling used in an American bridge project.
Both types of piles were used side by side in a difficult environment. The bridge crosses a riparian marshland, an environment that is historically damaging to traditional concrete. Fortunately, Cor-Tuf UHPC (unlike traditional concrete) is nearly impermeable. The material is extremely resistant to water and environmental chemicals, making it ideal for use in these marshland conditions. In fact, we have independently verified chloride penetrability values of less than or equal to 100 using both ASTM C1202 and AASHTO T277 testing methodologies. This is a negligible reading. In our experience, standard concrete typically tests in the 800 – 1300 range.
Installation and testing of Cor-Tuf UHPC H-piling with the Florida DoT
Installation was uneventful. The UHPC H-piling cut through the subsurface strata with little resistance and maintained 100 percent integrity during the entire installation, despite enduring approximately 2 million pounds of pressure at its base. The pad between the hammer head of the D-62 hammer and the top of the piling actually caught fire (as it did with our square piling) and began to disintegrate from the friction between the two materials. The hammer was no match for Cor-Tuf UHPC, and the top of the piling was in no way damaged or compromised.
Cor-Tuf UHPC H-piling being hammered into the ground
The results from these and previous tests prove beyond the shadow of a doubt that Cor-Tuf UHPC is the only name you need to know for all of your UHPC needs. It’s the only UHPC on the market that can be mass produced with conventional methods, mixed and poured with traditional equipment, and is pumpable. We look forward to continuing to lead the concrete revolution and bringing UHPC to the masses.
