Concrete piles are most frequently implemented as integral support structures for construction projects, including tall buildings, bridges, and rigs. They are built according to predetermined configurations and specifications described in their design.
These deep foundations effectively transfer a building’s load to the underlying rock or soil, making it reliable even in unstable ground conditions.
What are Concrete Piles?
Concrete piles are generally made of concrete and steel and are used in a wide range of construction projects to handle heavy lateral and vertical loads and unstable ground conditions.
Concrete piles are installed up to the required depth or to that of load-carrying soil or rock layer. These piles are used in circumstances where the shallow foundation, including a spread foot, cannot provide adequate support due to weak or crushed soil.
Types of concrete piles
Concrete piles are generally reinforced piles and are classified into two categories based on construction techniques:
Pre-cast Concrete Piles
Pre-cast or pre-stressed concrete piles are cylindrical or tubular constructions made off-site and sent to the construction site after cutting. They are injected or driven in the ground using hydraulic hammers and other pile-driving equipment.
Cast-in-Situ Piles
These piles are constructed by pouring concrete into a drilled borehole at the job site. Cast-in-situ concrete piles are constructed on-site as per the design. Steel reinforcement can be added both before or after concrete pouring to achieve tensile strength.
When Concrete Piles Are Used?
- Weak or Unstable Soil: At the site of most construction projects, the soil is not always sufficiently strong or stable to bear the weight of a building, which requires the installation of concrete piles to transfer the load to deeper rock or a more resilient layer of soil.
- High Water Table: In the regions with a high water table, sometimes traditional shallow foundations are not the best solution, for they may become affected by changes in water level. The piles made of concrete can reach the level below the water table in order to create solid support for the structure.
- Heavy Loads: There are often considerable loads imposed on the buildings or structures that require deep foundations like concrete piles to support these structures successfully. For example, elevated buildings, bridges, industrial structures, or retaining walls.
- Soft Soil: In the case of regions with soft or compressible soil, concrete piles can be driven into the ground so that they can compress the surrounding soil while they are driven. Hence, the structure will be less prone to an uneven settlement.
- Seismic Activity: In the cases of earthquake-afflicted regions, concrete piles can be used to anchor the structures to the ground, reducing the risk of destruction and damage during an earthquake.
Overall, concrete piles are utilised when traditional shallow foundations are inadequate to support the loads and conditions present at a construction site, providing a stable and durable foundation solution for various types of structures.
Pros and Cons of Concrete Piles
Advantages of Concrete Piles
- Strength and Durability: Concrete piles bring in high compressive strength and durability, providing necessary support to heavy structures so that they can survive in harsh conditions.
- Ease of Installation: Another advantage of concrete piles is that they are easier to set up and can be done in less time compared to other types of piles like steel or timber, especially where the access is constrained, or the soil conditions are difficult.
- Resistance to Environmental Factors: Concrete piles are corrosion-free, rot-proof, and resistant to attack by any pest, hence suitable for marine, coastal, or industrial applications that are subjected to regular exposure to moisture or chemicals, among other reasons.
- Cost-Effectiveness: At first, basically for purchasing and installing, concrete piles are likely to offer long-term cost savings through their huge durability and low maintenance expenses over the entire lifetime.
Disadvantages of Concrete Piles
- Weight and Handling: concrete piles can be both cumbersome and heavy to transport. They also require specialised equipment for their installation, which ultimately leads to an increase in project costs and complexity.
- Environmental Impact: Concrete production entails a lot of fuel use and carbon dioxide emissions, thus joining the overshadowing environmental concerns of carbon emissions and resource depletion, which indeed contribute to global climate change.
- Limited Flexibility: When they are installed, concrete piles become less plastic than other types. Therefore, it is very hard to change and adjust their dimensions and specifications after the installation is complete.
- Potential for Cracking: Concrete piles that protrude through water can easily crack due to factors such as shrinkage, settlement, or external loads, making periodic checks and maintenance necessary. Inadequate preservation or monitoring can lead to compromised integrity of the structures.
Cost of Concrete Piles
The cost of concrete piles depends on the depth, dimensions and other design specifications, such as concrete mix design. It also depends on the accessibility of the location and the technique used to install piles. However, on average, a concrete pile for a domestic building can cost around £398.
Conclusion
Concrete piles are essential to supporting structures in various projects, from skyscrapers to offshore platforms. They are designed to provide safety and stability in demanding environments.
Their adaptability to different ground conditions and capability to endure heavy loads make them irreplaceable in construction. Nevertheless, factors such as environmental effects and the complexities of their handling must be considered during their deployment and operation.
Despite these difficulties, concrete piles’ effectiveness and reliability still make them one of the most common choices for the construction of deep foundation support.