Sheet Piling and Pile Hammers: What Equipment is Best?
There are many different types of pile driving equipment for many different applications. This includes the pile hammer, the vibro hammer, the sheet pile hammer, the hydraulic sheet pile driver, and many more.
But what do you do when you don’t know your vibro hammer for sheet piling from your hydraulic pile hammer, or the different sheet pile driving methods? With that in mind, we have put together a guide about the wide variety of sheet pile driving equipment and sheet pile driving machines.
What is a pile hammer?
To understand the purpose of a pile hammer, you first need to look at what a pile is.
A pile is a postlike object that is driven into the ground to support building works. In the context of canals, piling is most commonly used to provide a retaining wall between the bank and the water, reducing bank erosion. Sheet piles are sections of sheet materials with interlocking edges that are driven into the ground to provide earth retention and excavation support. Sheet piles are most commonly made of steel, but can also be formed of timber or reinforced concrete. The most common piles are steel sheet, as it can provide a long-term solution for over 25 years.
These walls are otherwise known as sheet piling, and they are crucial to providing vertical, stable bank during waterside construction work. A collapsed bank can lead to a wide variety of problems for building professionals, and sheet piling in water provides a barrier to prevent it.
But in order to drive sheet piling into the ground, you need sheet pile driving equipment. This is where a pile hammer is required. Whether excavator mounted, mounted on another machine or hanging off a chain, a pile driving hammer pushes piles into the ground with sufficient force to render it stable.
What are the different types of pile hammer?
There are three main types of piling hammer. A vibratory pile hammer uses vertical vibration to move adjacent soil, reducing the ground’s resistance. Vibratory pile drivers can vary in size – the smallest offered by the Rothen Group can be used to drive trench sheets, short lengths of plastic piles, wooden posts, tubes and plastic piles. The Rothen Group’s largest vibro hammer for sheet pile driving can be excavator mounted on machines between 13 and 25 tonnes, and is ideal for mid-heavy duty piles and pile walls.
A vibro hammer is a comparatively quiet and effective means of driving steel sheet into the ground. A free-hanging vibratory hammer can offer further reduced noise levels, and does not need to be plumbed into the crane’s hydraulics.
By contrast, hydraulic impact hammers are comparatively louder, but are more environmentally friendly to use than diesel hammers. A hydraulic hammer can run directly from the hydraulic system of the machine it is mounted on, or through a standalone hydraulic pack. This sort of piling rig is highly efficient and has a low operating cost.
Air pile hammers are often the preferred choice for canal and river restoration projects where driving piles in water is required. Robust, versatile and easy-to-use, they are ideal for trench sheeting, driving light pile sections, plastic piling, barrier and fencing posts, or timber piles and posts. They are appropriate for use on both hard and soft ground.
What is your preferred sheet pile driving method?
Generally, the piling hammer is excavator mounted or mounted on a crane, with the sheet piling process being carried out from the canal or river bank. Sheet pile driving equipment can also be operated from floating plant on the water, such as powered excavator pontoons or narrow beam crane pontoons.
We use a piling frame to set the line of piles to ensure the piles are driven straight, however curves can also be created by piling without a frame. This process is then repeated until the entire canal or river bankside is stabilised. A common sheet pile driving method involves what is commonly called a back tied system.
In this system, you have a tie rod that bolts to the front of the pile and a type of pile called an anchor pile at the back, which is driven in by a pile hammer to hold all other piles in place.
Often, a metal waler is used in conjunction with piles and trench sheeting to provide extra support. A waler is a compact, hydraulically expandable retaining wall, often resembling a steel sheet, which is used to bolster both sides of the waterside trench dug during bank excavation work.
This trench can then be ‘backfilled’ with Type 1 aggregate before being finished with concrete, with mooring rings, lay coping or other appropriate finishes. This provides a solution that will prevent bank collapse in the long term, whilst matching the aesthetics of the surrounding area.
What are the different issues workers may face driving piles in water?
Between sheet piling in water, the types of pile and the different types of pile driving equipment and sheet pile driving methods, there are a wide variety of issues workers can face.
Logistics are a key issue when organising projects involving driving piles in water. Everything from the retaining walls needed to the equipment needed – vibratory pile hammers, double acting hammers, drop hammers, hydraulic pile drivers, etc. – needs to be transported to site. Equipment suppliers such as The Rothen Group can transport all sheet pile driving machines and assorted supporting equipment to the required location quickly via the waterway itself for a quick and efficient solution.
The site’s size and location may also offer restrictions on the size and types of pile driving equipment and plant solutions used. Our wide variety of equipment and ability to transport and use solutions on the waterway allows us to provide a bespoke solution regardless of site accessibility or ground conditions. However, issues such as hard rock, nearby rubble or loose sand do need to be considered before sheet piling in water can occur.
Noise levels also need to be taken into account when carrying out bankside work, and this may affect the type of pile driving equipment specified. For example, a hydraulic impact hammer may disturb nearby residents more than a vibro hammer. As such, hydraulic piling and sheet pile driving methods involving this type of sheet pile driving machine should only be considered in more remote areas.
Finally, you need to consider that a canal is a 200-year-old structure, so any solution involving sheet piling in water should look to preserve the waterway’s integrity. Incorrectly specified pile hammer equipment could lead to a host of problems, including collapsing banks, and even water leaking out, which can cause the canal to dry up.
What is the process around ordering sheet pile driving equipment?
We can often mobilise any necessary equipment within 24 to 48 hours, depending on availability and manpower. Our experts will first go to the site and advise you on how long any bank stabilisation work will take, transport logistics, and whether on-site expertise is required alongside the equipment.
As part of this process, we can advise you on the best option for piling, including whether a back tied system would be suitable, or a cantilevered solution without back ties or anchor piles, the type of piling hammer required, and the best backfill option. This can all be done by the waterside, before the work is carried out.
If you have any further questions about dredging, or would like to know more about the services The Rothen Group can offer, please contact us on 01827 215715, or email email@example.com