When you’re managing a construction project on an area that lacks sufficient load-bearing capacity, pile foundations provide a valuable alternative. Able to transfer the weight to deeper, more suitable soil structures, piles open up the building potential of a range of conditions. But you still have to find the right piles for the land and the project. And for many, the decision often comes down to a choice between screw piles and steel rammed piled. So, what do you need to know?
Screw Piles vs. Steel Rammed Piles: The Pros and Cons
What is a screw pile?
Screw piles are large, hollow high-strength steel cylinders with a helical flight running around the exterior. They are embedded in the earth in much the same way that a screw becomes embedded into wood, rotated to the desired depth. Either using a groundworks vehicle, depending on the nature and location of the project.
What is a steel rammed pile?
Again made from high-strength steel, steel rammed piles are installed using hydraulic pile drivers. This is a specialist piece of equipment that must be procured specifically for this job. Often large and noisy, this machinery can work quickly, driving up to 250 piles a day. But this is only viable on sites with plenty of access and space to accommodate the equipment.
What are the pros and cons of screw piles and steel rammed piles?
The pros of screw piles
- Screw pile installation can be extremely fast. This enables adaptive installation, according to the needs of each site.
- Once installed, screw piles can be used immediately.
- There is very little ground disturbance created by screw pile installation.
- Screw piles installation also causes minimal noise pollution.
- Screw pile torque can be measured during installation to ensure accurate load-bearing capacities.
- Screw piles suit a range of environmental conditions, and can even be installed in water and flood-prone areas.
- Screw pile installation causes no spoil, reducing later waste disposal costs.
- Screw piles can be easily removed and recycled at a later date.
The cons of screw piles
- Poor installation protocol can compromise the integrity of the screw pile. So always ensure you employ a competent installer.
- Some conditions are not suited to screw pile installation. As a rough rule of thumb, if the grain size is more than 60% of the pitch of the helices, screw piles should not be used.
Pros of steel rammed piles
- With the right equipment, steel rammed piles can be installed extremely quickly.Once installed, steel rammed piles can be used immediately.
- Steel rammed piles are pre-formed, with an interlocking system, which enables piles to be adjusted when required.Steel rammed piles are strong and durable and suited for a range of environmental conditions.
- The installation of steel rammed piles is also spoil-free.
Cons of steel rammed piles
- Because specialist equipment is required for the installation of steel rammed piles, they are not a good choice for areas with limited access or space.
- Steel rammed piles can be expensive, especially when you require large numbers of longer piles to complete a project.
- Steel rammed piles may not be suitable for use on land where there is poor drainage.
- Steel rammed piles may also be unsuitable for builds in built-up areas, where installation may cause ground disturbance and damage to adjacent structures.
Different piles are intended for different situations, and there is a place for all pile types within the construction industry. But finding the right piles for each project is integral to the success of the build. So, it pays to do your research before you begin.
Get in touch with UK Helix to find out more about screw pile foundations.