New Rowing Club a Model for Advanced Pile Foundation Technology

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

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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Determining the Cost of Helical Piles

engineers costing helical piles at an industrial facility

There are a number of factors which go into determining the cost of helical piles. Some are more obvious than others, but in the end, the chances of getting an accurate estimate will be much more likely when an experienced installer weighs the following criteria.

Geographical location of the job site

One cost factor which you might find a bit surprising is the element of geographic location. In a cost survey conducted by Helical Pile World in 2016, it became apparent that costs for the same kind of helical pile project would have a significant variance based on which part of the country work was done. Generally speaking, the more expensive pricing was in the Northwest and Mid-Atlantic states, while the least expensive cost of helical piles was quoted by companies in the Midwest and Plains states. So, if you have a project where helical piles will be used, the first cost factor will depend on which region of the country your project will be located.

Repair or new construction

The second most important cost factor in this survey is the type of project to be built. Participating companies universally quoted higher prices for remedial projects involving helical piles, as opposed to new construction projects with pile work. In many cases, the new construction was only about half the cost of the repair work.

After these two top factors, the cost elements tend to be closely related to the actual foundation installation work, which involves the piles themselves. We have broken these factors down as follows.

Number of piles

The number of piles needed on a given project is only partially determined by the size and footprint of the structure to be supported. The amount of piles necessary is also greatly influenced by the loading requirements, support requirements, structure type, and building codes applied to the project.

More importantly, because helical piles come in different sizes at different price points, one hundred piles of one size can cost less than fifty of another. The estimating contractor and the project engineers must be highly experienced in being able to determine how many of each size helical pile will need to be used.

Type of piles

The type of helical piles being used can also vary in diameter, shape and style, as well as whether they are being installed with or without grout.

The shape of the piles is either a square shaft or round shafts. Common square piles come in 1.5”, 1.75”, 2”, 2.25” and up. The common pipe piles come in  2 7/8”, 3.5”, 4.5”, 5.5”, 6.5”, 8”, 10”, etc. Typically, the bigger the diameter of the pile shaft, the more costly they will be.

Grouted shafts are a relatively new development in helical piles. As an anchor is being screwed into the soil, a grout column is gravity fed all around the shaft to reduce the likelihood of buckling under high stress. Such a technique is commonly used in soft soils, and has the effect of making the whole column much more rigid, while increasing the load capacity of the foundation itself. Grouted piles do not cost significantly more than un-grouted shaft installations, but can significantly improve performance. In many cases, small grouted square shaft piles actually cost less than un-grouted pipe shaft piles with similar loading capacities.

Once again, the type of pile used is very project specific and the best pricing will be determined by an experience estimator.

Depth of pile installation

The depth of the pile installation will influence the cost of helical piles simply because it takes more time and material to install deeper, more secure foundations. In many cases, anchoring will need to be drilled deep enough to a point where a more competent layer of soil resides. The load-bearing requirements of the project will also affect how deep piles need to be anchored.

For example, a pile going 40′ deep will add more to the material cost of a job than one going only 20′ deep. More pile extensions need to be added to the main shaft in order to achieve the greater depth. Installing longer piles also increases the time that drill crews need to be on-site.

Soil conditions

The design and selection of the piles being used for a specific project is directly affected by the encountered soil conditions. Buckling, liquefaction, density of the bearing layer to be penetrated, and density of the upper fill layers, all play a factor in which pile is chosen and the overall cost of the job.

In short, the soil conditions for a project will play a large part in determining the number, type, size and depth of piles to be used. As explained above, the choice of helical pile has a significant affect on the cost of helical piles material, needed for the project.

Cost of helical piles – The bottom line

Like all construction, estimated bids are subject to unforeseen developments. However, when an experienced contractor/installer/estimator work up an estimate for a specific installation of helical piles, and take into account ALL of the above considerations, you can be confident that the estimate you receive is realistic and accurate. Location, type of job (new construction or repair), the number, type, and depth of pile installations and the type of soil are all important factors. They, in combination, will determine your price and why only an experienced helical pile installer will be able to deliver a reasonably accurate figure for your project.

Need a quote on a helical pile job?

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How a Helical Pile Foundation Can Speed Up Your Construction Project

A helical pile foundation can lead to faster construction and less down-time

Not many construction projects have the luxury of an open-ended time frame for completion, and in fact most projects have an understandably tight schedule which has to be observed. In construction, as in virtually all businesses, time is money, and this is especially true when all other tradesmen and contractors are waiting for the foundation of a structure to be installed. In many cases, a helical pile foundation can greatly reduce the time-to-build.

At most times in the past, there was literally no choice but to wait for a concrete foundation to be excavated, poured, and to dry before all other tasks associated with building construction could get underway. However, that model is changing more and more these days, as the advantages of a helical pile foundation become more universally known and understood.

When are Helical Piers Faster?

First and foremost, helical foundations are almost always installed more quickly than other piling methods such as caissons or driven piles.  While some common applications include support for bridges, boardwalks and industrial piping, engineers are constantly coming up with new ways to use helical piles as a time-saving alternative. Particularly useful for construction in wetland or flood-prone area, replacing a concrete foundation with helical piles can shave weeks and even months off a project.

One of the biggest advantages, especially for light industrial, temporary or above-ground structures, is the speed at which a foundation can be installed using helical piles.

How do Helical Piles Save Time?

Right from the very first step, helical piles save valuable time in the implementation of a foundation. No large excavating equipment is needed for the installation of the piles themselves, so as soon as engineers have tested the soil to determine the degree of anchoring which will be needed. A helical pile foundation can be screwed directly into the ground with machine-mounted hydraulics or machinery fitted with electrical drilling equipment. Almost any type of soil or ground is suitable for helical piles, other than bedrock itself, so virtually all locations are acceptable.

An aspect of helical pile installation which shouldn’t be overlooked is the actual installation itself. As piles are being augured into the ground, the rotation rate ranges anywhere from 6 to 10 rpm, which allows progress to proceed at roughly 2 feet per minute. That means that an anchoring requirement going 50 feet deep could be completed in less than an hour. Once all piles are in place, they can be used for load-bearing immediately, as opposed to having to wait up to a month for concrete to be cured, or grout to become dry.

At the end of installation, there’s also no major cleanup to be done, as there might be with any other kind of foundation installation. Installing helical piles is a very clean operation, which minimally impacts the surrounding environment, and does not require that excess soil be carted away in trucks to some other location. This itself saves an entire step which would be necessary in a major excavation, which in turn reduces the overall time needed to complete the foundation.

How do Helical Piles Keep Costs Down?

The bottom line is that when helical piers are used to anchor a new structure, there is no waiting for other construction processes to begin. Unless concrete footings or grade beams need to be poured, other aspects of construction can begin on the same day that piers have been secured. It would be hard to over-estimate the impact this can have on any kind of new construction project, since so much time is saved by the speed of installation, and the immediate readiness for subsequent contracting tasks.

Keeping costs down on a construction project can be the difference-maker on how profitable it is, and one of the most important ways that costs can be effectively managed is by reducing the overall time frame necessary for completion. There are several other very important advantages to adopting the installation of a helical piers over some other process for foundation installation, but when you’re thinking about your project’s bottom line, speed is one of the most compelling reasons.

 

Ready to speed up your next project? Talk to Conte

 

Building in a Flood Zone: 5 Tips for Hurricane Construction

Building in a Flood Zone - Tips for Hurricane Construction

When the weather turns downright dangerous, like it did with recent Hurricanes Harvey and Irma, saving lives is the number one priority. But when the wind finally calms, the rain finally stops and the skies turn blue, we look at property damage to evaluate how bad a storm really was. Victims of lost homes and other property damage need to know how to repair the devastation left behind and how to prepare for building in a flood zone in the future.

You’ll find our list of tips for hurricane construction below, but first, we want to show you why we feel so passionately about preparing for hurricanes and flooding through proper construction techniques.

We talked to Matt Conte, our 3rd generation owner of Conte Company, who understands that storm repairs are about more than just fixing houses. It’s about coming together as a community to help put people’s lives back together and get things back to normal. As we keep those in Houston and Florida in our hearts and minds during the devastating aftermath of Hurricanes Harvey and Irma; and as we prepare ourselves for a less ferocious Hurricane Jose in the Northeast, we can’t help but think back to two storms that ravaged our own community, just a few years ago…

The two storms that changed the way we think about coastal construction in New England…

Hurricane Irene was the storm that hit the East Coast of the United States during late August 2011 and ranks as the eighth-costliest hurricane in United States history. Here in CT, Irene dropped a devastating amount of rainfall, washing away roads, bridges and anything else in the flooding rivers’ path. Some major highways were closed for days and more than half the state lost power. But Irene couldn’t compare to Sandy, which arrived a year later. 

Hurricane Sandy (a.k.a. “Superstorm Sandy“) was the second-costliest hurricane in U.S. history, affecting 24 states, including the entire eastern seaboard from Florida to Maine. New Jersey, New York and Connecticut were hit particularly hard. All said and done, damage in the United States amounted to $71.4 billion.

Sandy completely destroyed thousands of Northeastern shoreline homes, and in some cases leveled entire neighborhoods. In cities that were completely unprepared for such an event, streets, tunnels and subway lines were flooded and made transportation impossible in one of the most populous metropolitan areas in the world.

“At Conte Company, we remember all too well the damage that these two storms inflicted. We were there in the days that followed, surveying the damage and helping people figure out what to do next. As one of the premier pile construction companies in the area, we had a unique perspective and a service that was suddenly in high demand.”

Helical pile foundations can help prevent hurricane damage

There were lucky ones too… But even many of homes with little damage needed to be raised to comply with new flood zone regulations and insurance requirements. In some areas, the flood line was raised by as much as two feet, which may not seem like a lot, but when it comes to flood-prone construction, every inch can make a difference.

Some were extra-un-lucky… Many houses were built on deep pile foundations and survived both storms, but many did not learn their lesson after the first one. Only one year after Irene’s massive clean-up effort began, Sandy barreled through and again destroyed some of the homes that were just rebuilt. In most cases though, those homes were built on the same types of foundations that failed the first time around.

“We felt just awful for people that had to rebuild and lift their homes twice in one year, but these homeowners went through even more hell when FEMA ran out of money after Sandy.”

Financing from FEMA decided whose houses were fixed and whose were not…

Immediately after Irene, FEMA money arrived quickly and homeowners poured all available funds into new construction. Conte Company helped many dig out and lift their homes quickly with new pile installations and the region recovered relatively quickly.

But the story was very different with Hurricane Sandy which pounded the East Coast just a year later. At first, FEMA was very responsive to Sandy. As long as a homeowner’s claim seemed legitimate, the money came through and people could hire contractors to rebuild and lift their homes. But soon, Sandy projects started taking an unusually long time to get financed… FEMA was simply running out of money. After two back-to-back, very deadly, very destructive hurricanes, they could not meet their financial commitments to ill-fated homeowners who were building in a flood zone.

For some, there was a government program called the Superstorm Sandy Relief Fund, which tried to help a few homeowners in the direst of straights. But today, many who did not qualify for this program have homes which still remain condemned, with “NO OCCUPANCY” stickers plastered to the front door.

Rebuilding homes that are literally and figuratively “underwater”…

When homeowners in this region did not receive the funds they expected, Conte Company knew they had to play a big part in the recovery process, for the sake of the community.

“In many of Connecticut’s beachfront areas, many homeowners were first wiped out by Irene, then by Sandy and then by FEMA’s dried up funding.”

Homeowners were holding onto properties with negative equity, and banks generally don’t refinance a home in that type of financial situation. Conte Company knew up front there wasn’t going to be a lot of money for repair, but felt duty-bound to help a community that has supported their business since the 1940s.

Conte Company took it upon themselves to work with a number of general contractors. Ones they knew could do the job the right way, make honest recommendations to homeowners and wanted to give a little back to a hurting community. They were able to lower their own subcontractor rates in order to assist these hand-picked GCs, who working hard for Sandy victims, to rebuild some homes, and help some people put their lives back together.

“In some cases, we lowered our pricing more than we should have, but if we didn’t, the competition would come in and do an inferior job. We couldn’t have that. We wanted them to be happy again. With the repair and with us. But mostly with their lives.”

Many people are back in their homes today because Conte Company was able to help them with costs after FEMA’s coffers were empty. Unfortunately, Conte couldn’t help everyone — there was just too much damage. Thousands of homeowners who were building in a flood zone had to abandon their properties completely, as the cost to rebuild was just too high.

Building in a Flood Zone: How to construct a home that will survive the storm…

To this day, Conte Company is often asked to check homes that were repaired after Sandy by less-than-qualified builders. Many of the issues they find are (or will cause) significant problems when the next hurricane comes roaring through. Some of these homes’ problems were simply never addressed, not necessarily because those builders were dishonest, but more likely because someone didn’t understand, or care, what the real problems actually were.

In the wake of the most recent superstorms to slam the U.S., there is no better time to discuss these issues which apply to both new and existing construction. As experts in the industry, we thought it makes sense to give people our best advice and recommendations for hurricane-proofing your new home, or repairing your old one.

The 5 Most Important Tips for Hurricane-Proof Home Construction

1. Hire a Reputable Structural Engineer

No project is ever the same and there is no one-size-fits-all solution. Trust your project engineer to make appropriate recommendations about your home’s foundation. Don’t have one you can trust? We work with plenty and are happy to refer you.

2. Lift Your Home Above the Floodline

Building in a flood zone can be somewhat nerve-racking for a homeowner, but you can greatly limit your potential for damage simply by making sure it’s out of the floodwater’s way. Most of the real damage is done by high waters and the pounding surf of wave action, not by high winds.

3. Use Helical Piles for Deep Foundation Support

As some of the most versatile pile types around, helical piles can be installed in just about any environment. When properly designed, helical piles can also provide:

  • excellent lateral load to resist winds in high-velocity zones
  • substantial uplift capacities to keep your house from floating away
  • exceptional scour support incase of soil erosion below your house
  • and here’s some more info on helical piles

4. Use Piles to Support Every Structure on the Property

Grade beams are a great way to connect all the piles for each structure to support the load with an interconnected system of foundations. Grade beams are installed below grade to create a solid foundation spanning from pile to pile. Every external structure should be connected, including the deck, garage, pool, stairs, patio, etc.

5. Don’t Cut Corners, Don’t Use Band-Aids

If you are building in a flood zone, remember one thing…

“Doing it once the right way, means you don’t have to do it twice later. Even if you do it cheap twice, it will end up being more expensive than doing it right the first time.”

Hurricane Damage?

Conte Company performs structural and site repairs like as underpinning, supports and responsible replacement of scoured material. Make sure the job is done right, so you don’t have to do it twice.

Call Conte Company Today

4 Types of Helical Pile Design: Advantages & Disadvantages

Every commercial construction project is unique. Each type of structure will require a foundation specifically engineered to account for the size of the job and the ground on which it’s built. For the same reason, helical pile designs span a variety of shapes and sizes to accommodate a wide range of applications and variables such as soil type, soil profile depths, pile loading type, pile capacity requirements, the type of structure to be supported, etc. There are dozens of sizes, shaft type, and helix configurations available to make sure the proper helical pile is used for the job.

When engineered correctly, a deep foundation anchored with the correct helical pile design will last for many years. Choosing an improper helical pile design can lead to devastating results.

Make sure you choose the proper pile configuration… Call Conte Company Today!

In this brief guide, we’ve outlined the 4 major categories of helical pile designs, including their typical implementations, advantages and disadvantages of each.

Solid Square Shaft

The square shaft is typically solid and capable of large axial compressive loads. The solid shaft is continuous at each extension and carries the load down through to the end of the pile. Square shaft extensions can also used in a variety of tension applications.

Typical Sizes: 1.5”, 1.75”, 2”, 2.25”

Advantages: In rocky and hard soils, square shaft leads are better at advancing without damage.

Disadvantages: Slender shafts do not resist lateral loads well and buckling can occur in soft soils due to the narrower width.

Round Shaft Pipe

The round shaft pipe helical pile provides a much wider diameter than most square shaft piles. The wider cross section provides better structural capacity where large moments, lateral loading, or buckling can be present.

Typical Sizes: 2.875”, 3.5”, 4.5”, 6”, 8”, 10″+

Advantages: Round shaft piles are ideal for softer soils and when there is potential for high lateral loads. The pipe shafts can be grout filled for added structural capacity.

Disadvantages: Larger shafts can be more difficult to penetrate very dense or rocky soils.

Square & Round Shaft Combo Pile

Typically a combo pile has a square shaft lead, followed by round shaft extensions. These types of helical piles are used primarily in compression applications where layers of hard soil are located deep under a softer surface soil. Square/round combo piles are often chosen for high water tables, grout restricted sites or for sites with soils that make them a more economic choice than a grouted pile configuration.

Typical Sizes: 1.5”/2.875”, 1.75”/3.5”, 2.25”/4.5″

Advantages: This combines the better penetrating characteristics of the square shaft with the large diameter round shaft extension to resist buckling and lateral loading.

Disadvantages: Extra material costs can make combo pile solutions a less economical solution than alternative helical piers. It is only necessary under specific circumstances.

Grouted Square Shaft

All square shaft piles can be fitted with accessories to add a grouted casing. This casing is typically 5” to 8” in diameter and can be cased in PVC or steel pipe, or just grout. The grout also creates skin friction with the soil that can help the compression and tension capacity of the pile. The larger cross section improves lateral capacities, bending moment, and buckling resistance strength when compared to the slender square shaft pile on its own.

Advantages: In some soil conditions, square shafts with grout casing are more economical than larger diameter round shaft pipe piles.

Disadvantages: In some cases, grout plates can have difficulty advancing into very dense or rocky soils. Grout may also be prohibited from certain projects, for example in wetland applications or a site which cannot properly accommodate grout-mixing on site.

Choosing the right type of helical pile design needs to be done by an expert!

These basic explanations offer guidelines for which types of helical piles are appropriate for various projects, but there are many variables that go into making an educated decision.

Contact us for a free consultation about your upcoming project

What is a Helical Pile?

What is a helical pile? and other questions about helical pier foundation solutions

If you’re in commercial construction, you probably know a lot about what happens above ground as you watch structures rise from the earth. What happens below ground, at the foundational level, might be more of a mystery to some. Helical piles are an important piece of underground construction technology which invisibly hold buildings and bridges in place. So what is a helical pile?

Helical piles literally do all the heavy lifting.

Below are some basic facts about helical piles. Once you understand what they do, what they’re made of and how they work, you’ll gain a whole new appreciation for these invisible, deep-foundation champions.

What Do Helical piles Do?

The purpose of a helical pile is to provide foundational support for structures of all types and sizes. Just like old-fashioned pile-foundations, helical piles (also referred to as screw piles, helical piers, helical anchors, etc.) are embedded deep underground in order to disperse the enormous weight which sits atop them. Multiple piles are installed to create a platform, on which a building, a bridge or any number of other large structures can rest.

You may also be wondering what is a helical pile for? Learn more about what helical piles do and how they’re used on our deep foundations page.

What are Helical Piles Made of?

Most helical piles are round hollow shafts or square solid shafts, extruded from steel and come in a wide variety of diameters and gauges, to serve different types of projects.

One or more steel screw threads (or helical bearing plates) welded onto the shaft, in order to supply ample downforce to the soil as it’s being screwed into the earth. Technically, this is what makes it a helical pile. The plane (or angle) of the screw is standard, although the size and shape can vary based on the application and soil specifications.

At the head of the pile is a shear lug, which fits machine-driven, rotary hydraulic attachments. These, in turn, are powered by small or large excavators, depending on the size of the pile.

For grouted pile applications, a lead displacement plate is fitted onto shaft extensions. This small disc pushes soil out of the way as it’s being screwed, leaving room for concrete to follow.*

 

What is a helical pile? a line diagram of a round shaft helical pile

How do Helical Piles Work?

Helical piles are installed by twisting them into the soil, just like a corkscrew is twisted into a bottle of wine. As the shaft of each pile disappears below the surface, additional extension segments are connected with bolted couplers and screwed into the soil as well—ultimately resulting in a single pile which can extend 100s of feet below ground.

In many cases, the steel pile itself is enough to meet the load requirements of the project. However, for more robust deep foundation systems, concrete (also known as grout) can be incorporated. In a grouted column, concrete is continuously poured down the sides of the column, following the displacement plate and encasing the steel shaft. This technique produces a reinforced pillar that will withstand the most extreme compressive, uplift, and lateral forces.

*Conte Company also helped develop the DRIVECAST™ Grouted Soil Displacement Pile (manufactured by HUBBELL-CHANCE®), which incorporates displacement functionality directly into the screw bearing plate.

 

So, what is a helical pile? We’re happy to answer any other questions you have…

Set up a phone call or a meeting with the helical pile experts at Conte Company today

Why Helical Piles?

During these modern times of engineering and construction, there are many different ways to do just about anything. This includes the selection of a helical pile foundation. Pile foundations have been used for years to support structures that bear on unsuitable soils. As equipment and methods progressed, so did the applications and installation of each type of pile. All of these options still exist because each site and project requirement is different. We have to weigh our options to decide what the safest, most cost effective approach to providing a pile foundation is going to be.

Helical Piles have been around for many years, even though most people still haven’t heard of them. They are screwed into the soil using a motorized auger torque driver, which is attached to a piece of construction equipment. The screwing method eliminates the need for vibration and aggressive impact to advance the pile into the soil. The Helical Pile simply screws into the ground. With the torque motor creating the force needed to install the pile, relatively small equipment can be used for helical pile installation.

The benefits of using small equipment can change the project in many ways. Some projects would otherwise be impossible, if not for the use of small equipment. Going inside buildings, basements, through landscaping, beneath lifted houses, high voltage, tight locations, etc. are all possible because helical piles require such small equipment to install. The reduced vibration and noise allow for businesses and daily activities to continue during installation, and the low emissions of smaller equipment help minimize any environmental impacts. Some older structures are so unstable, that any vibration will compromise their state. Helical piles can be used to underpin these structures without harming the current conditions.