Based on Load Transfer and Function, Different Types of Piles for Pile Foundation The following are pile classifications based on load transmission and functional behaviour: Piles that support the end of a building (point bearing piles) Piles of friction (cohesion piles) Friction and cohesion piles combined Piles that support the end of a building These piles transport their weight to a firm stratum located at a significant depth below the structure’s base, and they draw the majority of their carrying capacity from the soil’s penetration resistance at the pile’s toe. The pile should be intended to act like a regular column. Even on poor soil, a pile will not buckle, and this effect should only be considered if a portion of the pile is buckling.
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Cohesion or friction piles
Friction or cohesion is used to transfer load to the earth. However, the soil around the pile can adhere to the pile’s surface, causing “Negative Skin Friction” on the pile. This can occasionally have a significant impact on the pile’s capacity. The drainage of ground water and the consolidation of the soil generate negative skin friction. The results of the site investigation and soil test have an impact on the pile’s founding depth. Cohesion or friction piles The adhesion or friction of the soil in contact with the pile shaft determines the carrying capacity. Piles that support the end of a building.
The majority of the load is transferred to the soil via skin friction. The porosity and compressibility of the soil within and around the piles is considerably reduced by the process of driving them close together in groups. As a result, these piles are sometimes referred to as compaction piles. The earth is deformed during the process of driving the pile into the ground, and as a result, it loses some of its strength. As a result, the pile is unable to transfer the exact amount of load that it was designed to transport immediately after being driven. Three to five months after being driven, the soil usually regains part of its strength Piles of cohesion.
Cohesion piles and friction piles combined
These piles also use skin friction to distribute their burden to the ground. The method of driving such piles does not significantly compact the earth. Floating pile foundations are the most frequent type of pile foundation. Cohesion piles and friction piles combined When the bearing stratum is not hard, such as strong clay, the end bearing pile is extended. The pile is driven deep enough into the lower material to provide sufficient frictional resistance. Piles with larger bearing areas are another version of the end bearing pile. An extended base is created by pressing a concrete bulb into the soft stratum directly above the firm layer.
Bored heaps can have a similar effect by generating a huge cone or bell at the bottom with a specific reaming tool. Tension piles made of bored piles with a bell have a high tensile strength and can be utilised as such: Enlargement of a reamed foundation to a bore-and-cast-in-situ pile Piles are classified according to the sort of material they are made of. Timber, concrete, and steel are the most common materials used to construct pilings. When wood is available at a reasonable price, it can be utilised to make temporary piles. Steel piles are used for permanent or temporary operations, while precast concrete piles, cast in place, and prestressed concrete piles are made of concrete.
Piles of wood
Piles of woodIn areas where timber is plentiful, it has been employed for permanent works since the beginning of time. Long cohesion piling and piling beneath embankments are best done using wood. The wood should be in good shape and should not have been infested by insects. The diameter of the tip of a lumber pile less than 14 metres in length should be greater than 150 mm. A tip with a diameter of 125 mm is permitted if the length is larger than 18 metres. It is critical that the lumber is driven in the correct direction and not into solid ground. As this has the potential to harm the pile. The timber will be protected from deterioration if it is kept below the groundwater level.
Timber piles can be fitted with toe covers to protect and strengthen the pile’s tip. The most common way of preserving timber piles is pressure creosoting. Wood piles have both advantages and downsides. The stacks are manageable. In areas where timber is plentiful, it is quite inexpensive. Excess length can be simply removed and sections can be put together. The piles will deteriorate above the level of groundwater. Have a restricted capacity for bearing. Stones and boulders can easily damage the vehicle while travelling. In saline water, the piles are difficult to splice and are damaged by marine borers Piles of concrete. Concrete piles are classified as either prefabricated or cast in place: It is manufactured and strengthened in a high-quality regulated environment (precast concrete piles or prefabricated concrete piles).
Advantages and disadvantages
Within the pile, reinforcement is required to help it survive both handling and driving forces. Prestressed concrete piles are also utilised and are becoming more popular than precast concrete piles since they require less reinforcement. a) Detail of a concrete pile connection. b) a prefabricated concrete pile that is squared The Hercules type of pile junction may be readily and precisely cast into the pile and attached fast and safely on site. They’re manufactured of high-quality steel with precise dimensional tolerances.The ercules pile joint is a form of pile joint. A pile joint of the Hercules type. Precast concrete Piles + Stable in squeezing ground, such as soft clays, silts, and peats pile material can be tested before piling. They’re simple to splice. It’s a rather low-cost option.
Placement of the cast Concrete piles are the most prevalent type of foundation due to the wide range of options for pouring concrete and burying the pile in the ground. Driving and drilling piles are two types of cast in place concrete piles; however, difficulties such as arching, squeezing, and segregation can occur when these piles are installed. These piles are classified into the following categories: When lifting the tubes, piles are poured in with underneath heels and left. a few examples of these types: Simplex pile: A simplex pile is a cast tube with a diameter of 40 cm and an underlying heel that is hammered underground by an automatic hammer until it reaches arable soil for the establishment, after which concrete is poured within it.
Frankie Pile
The Frankie pile is a series of tubes that connect to allow easy access to enormous depths within the earth. To block the entry of cold water pipes, a reinforced concrete heel might be used and left in the ground. This pile can support a 50–80 tonne load.Vibro pile: A steel pipe with a diameter of 40 cm and a conical heel with a separate flange is hammered underground by an automatic hammer until it reaches arable area for the establishment, at which point the heel is withdrawn and placed in a tube, and concrete is poured. To compact concrete, the tube is pushed up and down (approximately 80 times per minute). This pile can support up to.
Depending on their function, piles are classified as bearing piles, friction piles, friction-cum-bearing piles, batter piles, guide piles.
construction methods which are driven piles, cast-in-situ piles, and driven and cast-in-situ piles.
A pile installed before the main piling works.
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Methods of Installing Pile Foundations