WHAT IS SHEET PILING?
Sheet pile is long structural profiles with a clamping system that creates a vertical steel wall to the area to be excavated by applying to the floor in a dependent manner. Sheet piling is generally used to hold soil or water. The performance capability of the sheet pile depends on the geometry and the type of floor on which the application is made.
There are permanent and temporary applications. Permanent sheet piles remain in the ground and serve as permanent stand structures. Temporary sheet piles are designed to provide a secure work and passage area inside the excavation and then they are removed.
Hot rolling and cold forming are the two main methods in the production of sheet piles. Although there are fundamental differences between these two methods, the most important difference is clamping. Since hot-rolled steel piles are produced from steel at high temperatures, the clamping tends to be tighter than in cold forming. Normally, looser clamping is not recommended for extremely demanding conditions or for walls that require low permeability.
Hot-rolled steel piles are generally bigger and have a greater range of strength than cold-formed steel piles.
Sheet piling is the most common application due to its advantages over other bracing methods:
- High resistance to pile driving stresses.
- Can be reused in several projects.
- With a little protection, it has a long working life both under and above water.
- Easily adjustable by welding or bolting and pile length is ensured.
- Connections tend to be less deformed during piling.
- It is constructed
- By arranging a steel pile profiler sequence and clamping the steel piles,
- By piling (or vibrated) the steel piles individually at the desired depth,
- By piling second steel pile with clamps between first steel pile second “clamped” one,
- By repeating 2nd and 3rd steps until the wall circumference is completed,
- By using connectors when more complicated profiles are used.
- Profiles can rarely be used as part of a permanent build.
- The application of steel piles is difficult or sometimes impossible in rocky or stony soils. In such cases, the desired wall depths may not be reached.
- Excavation profiles are determined by the steel pile profile and clamping elements.
- Piling of steel piles can cause discomfort to the neighbourhood.
- The settlement areas in neighbouring lands can be affected by piling vibrations.
The area where the sheet pile is to be applied should be observed and examined the suitability of the area in advance. The data which is going to be taken in this observation; if the application area is suitable for sheet piling machine, if there are any, check of the floor study reports of the application area, if not, floor type should be observed superficially.
Preliminary calculations are made considering factors such as excavation values, soil type, etc. before starting to sheet piling and the sizes of sheet piles, which is going to be used, is calculated. Afterwards, appropriate piling equipment (excavator mounted, variable moment vibeodrivers or diesel hammer) is determined according to sheet pile sizes and friction values taken from the ground.
Once the pile driving equipment is prepared, the placement of the sheet piling begins according to the construction drawings. To ensure that the sheet piles are correctly aligned and hammered, temporary laths, templates or guides can be created.
Once the sheet piles have been placed their positions, piling starts with proper pile driving equipment. To ensure that the sheet piles are not damaged and that are properly fastened over their length, flat piles should be piled by a proper hammer size and approved methods. A protective cap is attached to the top of the flat piles to prevent damage during Diesel Hammer operation.
Once the sheet pile has been dug into the floor, if the employer notices that additional penetration is needed, the addition and assembling work is carried out. Piling work is repeated until the sheet piles reach the maximum piling depth of the floor. Thereafter, the excess of sheet pile is cut off and removed from the field. All cutting work must be carried out regularly and professionally for safety purposes.
After completion of the sheet piling, the area between the sheet piles and construction is filled with suitable filling material and prepared for the removal. After the completion of filling process and necessary working area, which will be provided by the employer, is assigned for the machine, the dismantling process is initiated and removed from the site.