What are precast concrete piles used for?
Precast concrete piles are factory-cast foundation elements driven or installed into the ground to transfer structural loads down to stable soil or rock. They are widely used in bearing pile foundations, contiguous and secant piling walls, and marine or waterfront structures where a controlled, consistent pile section is needed.
National Pile Croppers supplies croppers for the full 150mm to 500mm square range, including the Pre-Cast Croppers for 300mm to 500mm piles, giving a clean, level cut ready for pile caps or ground beams without the vibration and debris of breaking.
What size precast concrete piles can be cropped?
Square precast concrete piles from 150mm to 500mm can be cropped with the right cropper from our range. The Pre-Cast 400 covers 300mm to 400mm piles and the Pre-Cast 500 covers 350mm to 500mm, both from a 6-tonne excavator, each taking around 250mm off per pass.
How precast concrete piles are driven
Driven piles are created by hammering piles into soil up to a depth of more than 40m.
This is done using adjustable hydraulic or diesel hammers. It's considered a versatile option, suitable in a variety of ground conditions.
A pile of this sort can be used as the basis for engineering structures. This is true across industries, and suitable in most conditions. Precast concrete piles are suitable when dry strata overlap soft sediment. They also work well and in aggressive or contaminated soil.
Precast concrete piles are used for constructing various civil engineering and construction structures. They are customisable via pile cropper, suitable across a huge range of applications and ground conditions. This is especially true when reducing these items to the recommended pile cut off level. In this way, they present a cost-effective piling solution, which goes a long way toward explaining their longevity in the industry.
Installing without significant decay or material byproducts, concrete piles offer a lot. But where are these piles best used? Why are they still such a staple in their respective construction industries? And what is it about them that makes them so special, anyway?
Join us as we unpack one of the most versatile piling systems in effect, today!
What Are Piles?
In construction, precast concrete piles are usually square or hexagonal tubes or tube segments. They feature solid cross-section designs for short and moderate length units. They are also built light, by hollowing out the interior in hexagonal, circular or octagonal sections. The result is a pipe section that saves weight and can stand up under high pressure.
Once driven into place, each pile's interiors can also be filled with concrete. This adds structure for better overall reinforcement and weatherproofing. This is especially crucial where piles experience severe frost action, as it helps prevent them from cracking.
Drainage holes may also be created to stop water accumulating in the hollow interiors of the pipes themselves. Piles that carry applied loads in end-bearing, predominantly, should drive through soft clay and into dense sands. They'll also require economies in concrete and weight reductions so that handling works as it should.
What are the Advantages
In general, precast concrete piles can withstand high-tensile as well as high-pressure loads. Traditional reinforcement can be used as tensile pressure. It also works well for horizontal moments for any additional material.
In the case of pre-case piles, the reinforcement inherent to their structure lends extra strength. This adds value in resisting bending during pickups, transportation, and loading. Bending resulting from lateral loads is also a thing of the past, thanks to their reinforced design. These can be built in various configurations, sizes, and shapes, specific to each unique project.
Worried about the capacity of your traditionally installed piles? Not to worry - using the phase diagram, you can determine this capacity so you are all caught up. Using this technique, multiple segments are utilised in order to organise and install piles, for long distances.
Land vs. Sea
This style of concrete piles can be found in use on marine and water-based structures, which makes sense. After all, these are scenarios where a driven or cast-in-place pile would be impracticable or, at the very least, uneconomical.
For land structures, the converse is true. Project managers will choose unjoint precast concrete piles over precast concrete. This is done for many reasons, but the main is a financial one. They are generally less costly for two main reasons:
- Precast piles require precast reinforcement. They need this in order to withstand any bending or tensile issues that may occur during handling. After the pile has been put into the ground, however, most of this extra steel will not be needed, especially where compressive loads are applied.
- Precast piles will not be readily cut down for whatever variations they may need.
That said, there are a number of situations where precast concrete could actually serve a land structure better.
The different Uses available to you
In cases where large numbers of piles need to be installed, in easy-driving situations, this rapid driving may result in a cost savings. The efficiency with which these piles are installed outweighs the cost of the steel reinforcing, in these cases. Either way, reinforcement may actually be a necessity, in order to resist stresses from lateral and uplift loads.
Driving high-capacity piles into a hard stratum? You can expect to see another significant saving in the quantity of your concrete. This is especially true when compared to cast-in-place piles. This comes as a direct result of the higher working stresses which can be applied to these units.
When these drive into ground bearing sulphates, we find dense, reliable concrete.
As we can see above, the range of applications for precast piles made from concrete is still high. Specific to projects where the costs of a precasting yard can be mitigated by spreading them out, there is more than enough reason to consider them.
Piles may be designed and formed from standard reinforced concrete. For extra strength or flexibility, the forms may also be pre-or-post-tensioned and prestressed. Ordinary reinforced concrete piles tend to be preferred for any project where a fairly small number of piles is all that's needed. When the expense of a full production line for on-site prestressing isn't justifiable, these units are far more economical as well.
Ever reliable Pre-cast Concrete and Piles
In many industries, precast concrete piles are still, by-and-large, the preferred choice. This is seen most in the building of permanent, durable foundations. This is largely due to its outstanding adaptability and corrosion resistance.
It's also a versatile option, with piles that can be spliced together in order to create longer piles. This is actually one of the primary areas where these piles are used. Transporting segmented piles in order to create structures of any length opens up dozens of possibilities.
Looking for more on everything from pile cropping and the best cutting equipment to concrete pile foundation? Check out some of our other insightful blog content today.
Alternatively, reach out to us to find out more about our market-leading pile services.
