Types of Pipe Piling

               Pipe piling is used transfer the loads of structures from shallow, weak soils unable to support such a heavy foundation to stronger layers that are found deeper underground. Pipe piling is driven into the ground either open ended or closed ended. If it is open ended, soil is able to enter the tube or it is filled with concrete to provide additional support or capacity to the structural foundation. There are several materials available that are used to manufacture pipe piling including: Steel, timber and concrete. Each are equipped with various advantages and disadvantages, and deciding which to use relies mainly on the intended project for the product. Knowing some basic information and which benefits these different materials presents to consumers makes it much easier to choose the product specific to their needs.

Steel

               Steel is a popular choice for pipe piling application because of the many advantages it provides to consumers. One main advantage is that steel pipe piling come in a wide variety of sizes while pipe piling made of material like timber which is usually manufacture in shorter lengths. Steel is a widely-used choice because of its sustainability in hard-driving projects, and it is also easier to drive than other materials – especially through harder soils. Another benefits includes a minor displacement of the soil when steel in the chosen material. While there are a lot of advantages to steel, there also some downfalls. It can be costly and it tends to corrode. It also can present more challenges during delivery and is much louder to drive than a material like timber.

Timber

               Timber piles are constructed of wood, and due to the material wide availability piles made of timber are usually not as expensive as other material like steel or concrete. While the cost of timber piles is definitely an advantage to those utilizing the product, some timber piles – depending on the type of wood used and the source – may not be the most suitable choice for heavier loads. Other advantages to choosing timber include that it is easy to handle and made of wood – a material that doesn’t corrode. Also, in most cases timber pipe piling is resistant to decayed if it is fully driven into the ground but it may require treatment beforehand to prevent damage from decay and insects, which can be a disadvantage to some. Another disadvantage is timber piles are more likely to be damaged during driving.  

Concrete

               Lastly, concrete pipe piling is another available choice. Some positive aspects of choosing concrete are that it is relatively inexpensive and resistant to corrosion – unless utilized in marine applications. It is also a good choice because the length of concrete pipe piling can be easily adjusted to match customers’ specifications and it as a low level of noise as it is driven into the ground. However, on the flip side concrete does have some disadvantages to the consumer. It is hard to handle and transport, and splicing concrete can be a real problem.

What to Know about Pipe Piling

                    Structural pipe piling is a variation of steel used as a driven pile foundation. Having the capability to either be driven open end or closed end makes for a versatile foundation option. If driven open end, soil and other loose materials make their way into the pipe through the bottom. Pipes required to be empty for construction can simply apply pressurized water to remove the loose materials inside the pipe post driving. For closed end pipe piling, the bottom of the pile is covered with a steel plate or even a specially designed steel shoe.

                                    

                    Alternatively, some construction projects require the pipe piling to be filled with concrete. This is done in order to contribute increased resistance to corrosion. Some countries avoid this route altogether in order to cut costs. If this occurs, protection against corrosion is furnished by accounting for a sacrificial layer of steel or by utilizing a higher grade of steel pipe. When a concrete filled pipe piling corrodes, a majority of the load capacity of the pile remains intact from the concrete. In an empty pipe piling the structural load capacity would lost, therefore, no longer structurally sound.

                   Calculating the structural capacity of pipe piling is determined by the strengths of both the steel and concrete, if the piling is concrete filled. Depending on conditions of the construction site and/or building codes, a certain leeway is made for corrosion of the steel piling. 

                   Generally made out of newly manufactured steel, pipe pilings for deep foundation construction can even be made from reclaimed steel. Typically the reclaimed steel is tubular casing that had been used previously in the exploration of oil and gas.

                   On some occasions, the piling is driven into soil that runs a high risk of corrosion. To slow down the corrosion process and protect the steel from rust, either a coal-tar epoxy or cathodic protection is applied. Although, corrosion of the pipe piling is calculated and accounted for when deciding on the size and which grade of steel pipe to use.