New Rowing Club a Model for Advanced Pile Foundation Technology

by Conte Company

We recently spoke with Matthew Conte, of Conte Company, about a foundation project they completed for a 2-story rowing club in Norwalk Harbor. Rowing clubs often prove especially difficult to build due to their proximity to the water, and the ground on which they are built. Building near or above water brings its own set of challenges for pile foundation technology, along with strict guidelines to which builders have to adhere.

In the case of this building, the ground floor of the rowing club is to be used for storage of the boats and equipment, while the upper floors are used for meetings, offices and social areas. Crew has always been a mainstay in the Connecticut area and rowing clubs are an important piece in the community, serving as both an athletic and social gathering place. Matt and his team were eager to finished this project quickly and efficiently, in order to get the general construction started on the 6,000 sqft, pre-fab, metal butler building, so it will be ready for the upcoming season.

In order to build this rowing club, Conte Company installed 56 27′ Drivecast piles. They tied those piles to a grade beam grid, on which a heavy slab of concrete was poured. The soil conditions, which were waterlogged every time the tide came in and composed of organics, fill and silty material, were not suitable for traditional building. The engineering team ultimately determined that there were only a few cost-effective pile foundation technology options for a site plan like this. The only other alternatives to Drivecast were helical piles, or H-Piles.

According to calculations and field tests, utilizing helicals would have maxed out at around 40-50 kips (1 kip = 1,000 pounds of force), whereas each Drivecast pile supported a staggering 120 kips! Matt explained to me that the other alternative, using H-Piles, would require pile lengths of up to 75ft in length, and would’ve taken significantly longer to install. For starters, H-Piles typically come in 50 foot lengths, so each pile would need to be spiced together to produce the full 75′. What’s more, when you’re talking about driving piles of this enormous length, you need some enormous equipment to do the job. In this case? A massive crane would be needed to drive each of the H-Piles deep, deep into the earth. By contrast, Conte Company’s Drivecast piles only required a 14 ton excavator to get the job done. Matt explains it best:

“A 14-ton Ex looks like a toy, sitting next to a crane like that. We pulled up our machine on a trailer and were in-and-out of the job site quickly.”

Matt and his team installed all of their Drivecast piles within 5 days; start to finish, and had no issues installing them. The grouted columns were allowed to dry for 5 days before testing, and again had no issues, even in the salty, waterlogged silt. As an added bonus, the site was located on property owned by a chemical plant, regulations for which are far more stringent than other environmentally regulated industries. Again, no worries, Conte Company sailed through all requirements with ease. The entire project went off without a hitch.

The building Matt and his team recently built is located on Norwalk Harbor, and will be a great addition to the community. Matt and his team, along with the revolutionary pile foundation technology called Drivecast from Hubbell-Chance, allowed this project to be done faster and cheaper with less work, and smaller equipment than H-piles or helical piles.

What more do you need? Download the official Drivecast brochure below:

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What are Displacement Piles?

by Nate Kruska

Generally, displacement piles are load-bearing columns designed to be installed without spoil material (soil that’s removed from the ground). Instead, special equipment is used to displace soil laterally, compacting it into the surrounding terrain. While not ideal for every situation, displacement piles can sometimes support higher capacities than alternative helical piles or bored piles, as more of the load is placed on the grout and dissipated evenly into the earth.

Over the years, commercial construction engineers have created dozens of displacement pile styles, all of which are either pre-cast or cast-in-place, and most are either driven, drilled or screwed into the ground.

The most common and generally accepted types of displacement piles fall into the following 4 categories:

Precast Driven Displacement Piles

Preformed concrete piles have wide application in a variety of soil conditions. Concrete pillars are hammered into the ground until enough friction or an end-bearing point can support the required capacity. Because of the enormous force and violent vibration on the pile during installation, pre-cast driven concrete piles are almost always pre-stressed or reinforced in some way.

Pre-cast driven displacement pile

Cast-in-place Driven Displacement Piles

Another form of driven pile requires large, hollow steel tubes to be driven into the ground, creating a void to be filled on-site with concrete. These tubes are capped on the nose to force the soil outwards in the same way a nail is driven into wood. For uncased piles, the tube is removed while the concrete is being poured, and reused to form each new grout column. In other situations, the tube is left underground, as a permanent casing for the pile.

Cast-in-situ driven displacement pile

Cast-in-place Drilled Displacement Piles

Drilled displacement piles are similar to fully bored piles, except without the spoils. Specially designed displacement tools are drilled into the ground and force soil outward, creating a more compact and stable column for the concrete. Once the drill has reached the appropriate depth, grout is pumped in continuously as the drill is extracted. This ensures the column stays intact and the grout has a chance to fill every available crevice. A rebar cage is also typically used to reinforce the remaining concrete column.

 

Cast-in-place Screw Displacement Piles

As the name suggests, these piles are installed similarly to the very popular screw pile. Permanent steel pipes are twisted into the ground with specially designed screw flight attachments which also displace the soil laterally. As the pile spirals its way down, concrete is continuously gravity fed into the voided column. Once the piles has achieved its required depth, it is left there as reinforcement to the concrete column. This method is particularly useful in areas with limited accessibility, as only small machinery is needed to install screw piles.

 

Need advice on the right types of piles for your job?

Displacement piles are a valuable tool in an engineer’s toolbox when devising structurally sound foundations. Which style of displacement pile will depend on the project, soil conditions, load bearing requirements and accessibility for installation.

Talk to Conte Company Today

Don’t Delay Construction Until Spring: Helical Pile Foundations can be Installed in the Dead of Winter

by Conte Company

civil engineers at construction site plan on installing pile foundations in Winter

These days, there’s really no reason to wait through the entire frozen season before starting that major construction project you’ve been thinking about. The deep freeze which has held much of the U.S. in its grip this January might be a deterrent to building in some respects, but it certainly should not prevent you from installing pile foundations in winter, especially if you intend to use helical piles. When helical piles are being used, there’s simply no need to wait for the ground to thaw out – they can be installed in most frozen ground.

Installing Pile Foundations in Winter

Admittedly, there can be an added expense to winter installation of foundations, particularly if really frozen conditions prevail. Like almost every other outdoor pursuit in the dead of winter, there are special considerations necessary, which translate to a slightly higher cost for helical piles. For instance, in those cases where the ground is frozen solid, a more powerful pile might be needed to penetrate the frozen soil, after which it would be replaced with a ‘production pile’ for the actual foundation.

In really cold weather, it may also be necessary to keep concrete grout mixture warm for a period of time, after mixing and before it is placed in the ground. For this process, heaters have to be setup at the mixing site, and the concrete mixture must be entirely contained within this area prior to having it poured into the pile. While there would be some added expense associated with these measures, you can literally save months of construction time by installing pile foundations in winter, and not having to wait for favorable weather.

Pouring Concrete Foundations in Winter

It’s certainly possible to install concrete foundations in the winter, but some extra consideration is necessary for the whole process. For instance, the concrete supplier would have to mix the concrete with hot water, so it could survive the temperature drop when it comes in contact with the outdoor air.

Since it usually takes twice as long or longer for concrete to set in cold air, it might be necessary to use an accelerant in the mixture to speed up the setting process. It may also be necessary to install windbreaks or temporary enclosures, along with heating systems, to prevent the concrete from drying out too quickly, and to prevent sudden temperature drops from cracking the concrete before it has a chance to set.

Extra Installation Costs vs. Waiting Until Spring

If you really need to keep your building project on schedule, and don’t want to wait until a springtime thaw provides you with ideal conditions, you can definitely get your foundation in place during even the harshest winter conditions. And you can install a concrete foundation if you don’t mind all the added expense of winter excavation, warm concrete delivery, treatment with accelerants for fast setting, and all the protective measures that will be needed to maintain sufficient warmth for an extended period of curing.

The truth is, from almost every angle you look at it, employing helical piles offer significant advantages, especially in the winter. Even if you have your piles encased in grout, the concrete mixture settles below the frost line, where it can cure naturally without any artificial heat. And although larger structures typically require concrete slabs to be poured to complete the foundation, most of the foundational support lies well below surface, where temperatures are stable year round.

As always, there is far less disturbance to the surrounding area with helical piles, since they do not require any major excavation, and can be installed with much smaller equipment—this also allows for better accessibility for hard to reach areas. Installing pile foundations in winter can be done rapidly, and if there is ever a need to remove or replace them, that can be easily done.

Construction Doesn’t Need to be Seasonal

What would the financial cost be if you had to wait several months for warmer weather, before proceeding with your construction project? That doesn’t have to happen when you opt for installing helical piles during the winter months. With a cost that is only slightly higher, all the same terrific advantages can be realized by installing pile foundations in winter – with fewer worries about massive snow removal, properly curing concrete, or moving major pieces of equipment around on a construction site.

While everyone else is watching the snow fly and the ground freeze, you can be getting a foundation in place, and planning for all the other steps which follow afterward.

Ready to Start Thinking About Your Next Construction Project?

Talk to Conte Company. We can help you choose a stable, cost effective foundation for your next job.

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5 Innovative New Ways to Use Helical Piles

by Nate Kruska

Using screw piles for a playground's foundation and other ways to use helical piles

Many contractors already know about the tremendous advantages offered by using helical piles (or screw piles) as foundations for homes and buildings. But there are many more ways to use helical piles than just securing large structures in a variety of soil conditions. Some of these innovative applications are beginning to find favor with knowledgeable construction professionals and general contractors around the country.

Benefits of Using Helical Piles

It has long been known that helical piles are an ideal system to use in locations where the type of soil makes a traditional foundation more risky. Many residents of New Jersey discovered after Hurricane Sandy that helical piles could be used to great advantage for elevating their homes above storm surge levels, providing a level of safety and peace of mind.

Since installation of helical piles is generally much quicker than other deep foundation solutions, many builders appreciate using them when time constraints are involved with their construction projects. In neighborhoods of existing housing, where there is little room between buildings for equipment to operate, helical piles can be a much easier install than a conventional foundation.  The same is true for foundation repair work – helical piles can be installed much more easily in confined spaces.

Helicals are an ideal solution when building on water or wetlands. For typical construction, when building on good, dry soil, traditional concrete foundations are a cost-effective choice, but in certain situations, where the ground will be less accepting of concrete, screw piles are the perfect alternative.

Unlike most other foundation methods, helical piles can also be removed and recycled with very little effort. Since, in many cases, they were only screwed into the ground in the first place, it is only necessary to ‘un-screw’ them, and use them again somewhere else. The versatility provided by helical piles is unmatched in building circles, since they can be easily configured to adapt to removable structures, and provide tremendous value however they’re being used.

Finding New Ways to Use Helical Piles

The truth is, there are endless ways to use helical piles whenever any kind of anchoring or foundation is needed for structures large or small. In fact, they are fast changing the way that foundations are installed for many structures. It may be a cliché, but the only real limitation is a builder’s imagination and creativity. Here are some non-traditional ways we use helical piles…

Fencing Posts 

When fencing posts or deck foundations are attached to helical piles – they aren’t going anywhere. Even when fencing has to be setup in some marshy or soft soils, the fence posts can be attached to the mounting brackets on helical piles secured deep in the ground, where a stable layer of soil exists. Not only is there stability for the posts, but maximum support is also delivered.

Solar Farms 

As the demand for clean energy increases, so does the need for expansive solar farms around the country. There are a few fast, reliable, and cost-effective methods to anchor free-standing solar arrays,  including h-piles and helical piles. Both are capable of withstanding tremendous stresses applied by tensile, compressive, and lateral forces. With no real need for concrete, they can be installed very quickly, allowing more time for the other aspects of solar array construction.

When expanding an existing solar farm, it may be difficult to navigate big, pile-driving equipment around existing solar arrays. In cases like this, the small, agile machinery required to drive helical piles may be the only option. A mini-excavator is usually all that’s necessary.

Playgrounds

Of all the potential ways to use helical piles, you might not immediately think of a playground. However, anchoring a modern playground couldn’t be simpler than using helical piles. Mounting bracket can connect to the installed piles before securing the recreational equipment. With a totally reliable anchoring system, a playground can be made safe from all manner of forces which might act on it, and when children’s safety is an issue, total reliability is always the first priority.

Party Tents 

When you setup party tents in the same location time and time again for a recurring event, or series of events, it makes sense to provide a more permanent anchoring system for those party tents. The perfect solution to the problem is to install however many helical piles are needed to accommodate the number of tents which get erected, and simply attach the tents to the semi-permanent helical piles. Not only will there be great stability for the tents, but it won’t be necessary to re-invent the wheel for each year’s setup. As an added bonus, by using semi-permanent piles, certain styles of tents may allow you to eliminate or reduce the number of wires for patrons to trip over.

Boardwalks

Boardwalks are generally located in close proximity to some body of water, usually an ocean, and that makes securing them a bit of a challenge. Not a problem for an experienced helical pile installer. The boardwalk structure itself can be safely installed well above the normal water line, and can be attached with brackets to the piles. Flood-prone areas may even be zoned to mandate helical pile usage in the future, because they are so effective at anchoring structures on or around water. Also important to note is the eco-friendliness of helical piles for wetland boardwalks. It’s unmatched by other foundation methods, as there’s no grout necessary, no spoils from drilling and only the piles are left behind. As a result, the project has a very low environmental impact and poses no threat to surrounding wildlife.

Innovating Foundations Everywhere

Granted, not all projects are appropriate ways to use helical piles. But they are an incredibly useful and effective solution when construction needed to start yesterday. This is especially true for above-grade structures, when building on sites near water, and on projects with access limitations which can hinder larger machinery.

Conte Company has a line of Shallow Helical Piles, which cost less to produce and install than their larger counterpart. These shorter piles work in exactly the same way and are a great solution for all sorts of light-structure foundations. Our subsidiary company, Innovative Foundation Systems, specializes in pile foundations for fencing and solar, as well as other applications where concrete has traditionally been used. Contact us for more information.

Do you have a creative way to use helical piles?

Let’s talk! We can help you think it through…