Meta Title: Pipe Specs and Use Cases: Piling

Meta Description: Piling helps pack the soil by transferring the foundation weight deeper. This foundation building is essential in large-scale construction or repair work. 

What Is Piling?

Piling is a structure that can strengthen the deep foundation of any construction project. They are vertically inserted elements providing stability and support and can be made from concrete, wood, or steel. Piling transfers building loads farther down the surface by drilling or using a pile driver. 

This method is crucial when the soil around the construction site is too loose to provide adequate stability. Such shallow support weakens the foundation of the construction, making it vulnerable to accidents. When inserted on such loose earth, a piling pipe helps pack the soil tighter by transferring the foundation weight deeper. This foundation building is essential in large-scale construction like skyscrapers and bridges. 

Where is Piling Required?

Expert guidance is a huge bonus in piling projects because proper insertion is necessary for optimum stability. Geotechnical engineers ensure that the piles are driven into the ground at the right angle and at the precise spot to tighten the soil. These experts typically suggest piling in cases like

  • Piling is essential in large-scale projects that have very big design loads. They ensure that building loads get transferred farther down the surface where the earth is more tightly packed, offering more stability. 
  • Projects working on limited space can benefit from piling. This foundation-building method supports the building load even within a limited area because multiple piles can get driven to help strengthen it.
  • Geotechnical engineers typically suggest using piles to tighten the earth if the construction site has poor/loose soil at shallow depth. Depending on the usable area and the project requirements, the piles can be driven, drilled, closed, or open-ended. 

How is Piling Done?

In piling, pre-made, heavy-duty tubing is driven into the ground at specific angles and spots based on the recommendations of the geotechnical engineer. These pipes displace the soil on entering, and the friction and pressure result in a more compact and secure foundation. Driving machines like piles drivers and hydraulic hammers then hammer these piles into soil. Driven piles usually provide more support than drilled piles because they get inserted without drilling a hole in the ground first. 

Drilling pies have to possess a high amount of force and pressure resistance. These properties are crucial because hydraulic drivers drive them into the ground. These machines exert huge force to insert these pipes into the ground to ensure optimal soil tightness. The piles must be strong enough to withstand the onslaught of force to withstand this force. 

Since they remain underground, these pipes must also be resistant to corrosion, particularly those caused by moisture. Piling pipes are zinc galvanized, which helps provide an extra layer of surface protection from these elements. 

What are the Benefits of Using Steel Pipes in Piling?

The main purpose of piling pipes is to increase the bearing capacity of the soil. This role means the piles must transfer the load deeper down the surface. To do so, they must be able to bar the axial, bending, and shear stress caused by soil pressure. Though concrete piles are excellent for in situ application, steel piles generally are more versatile. These piles are made from durable steel, making them more resistant to earthquakes.

Steel pipes are particularly suited for marine application because they can be driven into the seabed with minimum soil disturbance. Steel pipes are used in on and offshore oilfield foundations, dockyard constructions, flyover/bridge projects, and more. Since these piles are pre-made, they require minimal tweaking, and their strength also makes them able to withstand the force of the driving process. 

Offshore Oil and Gas 

In seafloor oil and gas extraction, it is crucial to driving piles without agitating the surrounding seabed. Any disturbance of the loose soil causes problems with visibility which may hamper construction. Steel pipes help avoid this by causing minimum vibrations. They are also well suited for offshore oil and gas foundation building as their galvanized surface coating makes them resistant to seawater corrosion.

Another advantage of using steel pipes in piling is their ease of customization. If the project requires pipe lengths longer than the standard, multiple piles can be easily fused to create an elongated product. Depending on their use, they can get made from reclaimed steel tubing used in upstream oil or gas or new pipes designed specifically for piling.

What are the Different Types of Piling Pipes?

Piling pies are of two types, and depending on the degree of support required, developers either opt for open-ended or close-ended pipes. 

Open-Ended Pipes

The former provides a nominal amount of soil stability, as they have an open end at the bottom, through which soil is allowed to enter. Construction teams sometimes add concrete inside open-ended piles after hollowing out the soil inside to further strengthen the foundation. This addition improves the structural capacity of the pipe and also makes integration. Multiple concrete-filled pipes can get used as a large singular foundation by adding well-placed rods at the tops of these structures, enabling them to be integrated into upper structures.

Closed-Ended Pipes 

In contrast, closed-ended pipes have a cap at one end and typically provide more foundational support than open-ended pipes. They have welded steel plate bottoms or an iron shoe cast as a driving point, and for this reason, they are also known as plug-ended pipes. These pipes are used where the soil content is minimal, as their design enables them to provide increased friction and soil tension. 

Differences Between Piling Pipes

Type of PilingDriving PointCompatible Soil TypeAdvantages
Open-endedNo driving pointLoose soilImproves soil compression
Closed/Plug-endedYes/Or an iron shoeRocky groundStabilizes ground with less soil

Industry Specifications for Piling Pipes: ASTM A252 

For most standard construction jobs, ASTM A252 pipes of Grades 1 and 2,3 should work just fine. Among these ASTM Grade-3, pipe piles are the preferred variety because they have a tensile strength of 60000 psi and yield strength of 45,000 psi.

Length Requirements

The length specs for ASTM A252 pipes are as follows

  • Single Random Length (SRL)- 16 to 15 feet
  • Double Random Length (DRL)- Average 35 ft, with a minimum length of 25 feet.

Chemical Specifications

As for its mechanical properties, under ASTM A52 Specs, the maximum phosphorus content in piling pipes should not exceed 0.50%. This limit is necessary because this substance can make the steel brittle while adversely affecting the steel's welding capabilities. The other elements used in a pile should be administered according to the general requirements of carbon steel pipes. 

Tensile Measurements

GradeYield PointMin. Elongation at 2°Tensile StrengthMin. Elongation at 8° 
130000 psi30%50000 psi18%
235000 psi25%60000 psi14%
345000 psi20%66000 psi