When it comes to retaining earth during the piling and deep foundation process, sheet piling is the standard. It is commonly used for excavating or to provide protection from bodies of water. Sheet piling is also the most reliable and cost effective method to prevent shifts of soil or breeches of water from damaging the foundation or facility. Let’s take a look at how sheet piling works, safety and driving factors, and the types of retaining walls that can be used.
How Sheet Piling Works
The concept of sheet piling is pretty straightforward. Wherever a wall or siding needs to be held back, steel sheets are wedged into the earth at predetermined intervals. The sheets are driven into the soil with vibratory or impact hammers. In some cases they may be installed with hydraulic presses. The placed sheets interlock with each other, enabling variable designs that can be adapted for a specific retention job. If even more strength is needed, anchors are easy to add. The adaptability of the sheet piling means supports can be as temporary or permanent as needed. Sheet piling is used to protect or construct:
- Parking structures
- Seawalls and bulkheads
- Pump houses
- Below ground facilities
The Safety of Sheet Piling
When designed correctly, sheet piling can almost completely eliminate the risk of landslide, erosion, collapse or water breech. Construction sites are teeming with people and expensive equipment, so there really is no excuse for taking risks. With a simple survey, an optimal retention plan can be designed, minimizing construction costs just as much as safety risks. Properly designed and driven sheet piling can provide outstanding protection to construction sites and permanent retention walls.
Driving Sheet Piling
Driving steel sheets into solid ground is not a low intensity process. Using the right impact drivers is critical to make sure the strength of the sheets is not compromised during the process. Each material has its own recommended driving methods and hammers to avoid costly mistakes. It is important to ensure that any steel sheets are professionally driven according to manufacturer recommendations.
Types of Retaining Walls for Sheet Piling
Different sites need different walls. With each technique specifically designed for the scenario, the following are the most common retention walls:
- These walls provide support by the sheer strength of the sheets.
Braced and Anchored
- These are necessary for high pressure situations, increasing retaining strength with lateral braces and anchors.
- H-section pipes or piles are inserted into drilled holes.
Secant or Tangent Piles
- Drilled out sections are filled will soil to stiffen the walls.
Structural Slurry Walls
- Trenches are dug and filled with concrete as an alternative to steel.
Whatever site needs to be protected, there is likely a sheet piling solution appropriate for the situation. Investing the resources to have the sheet piling properly designed and driven can save the facility from higher costs down the road by getting the job done right the first time. STI group provides expert deep foundation and pile driving services and can assist clients in getting the sheet piling they need to thoroughly and completely protect their worksites.