When it comes to installing pile foundations, great care must be taken since they carry a substantial amount of load. The specific equipment and concrete pouring process used may vary depending on the size of the pile and the location of the structure.
If the borehole for the pile is dry, it is possible to pour concrete using any suitable method, as long as the falling height of the concrete does not exceed 2 meters. However, if the water table is high or slurry is used to enhance the borehole’s stability, tremie pipes should be utilized to pour concrete through the water.
The estimated volume of concrete required can be determined based on the number of piles, their diameter, and length. The choice of pumping machinery should be made based on the building’s location and the amount of concrete to be placed.
In summary, piles are essentially reinforced concrete columns that are drilled deep into a stable soil layer to support the weight of the superstructure.
How to Pour Concrete for Pile Foundation?
When borehole drilling is complete, it is important to start the concreting process immediately and to clean the bottom of the borehole beforehand. The volume of concrete and the type of concrete pump required for the job depend on factors such as the length, diameter, number, and location of piles. If the pile borehole is not dry, a tremie pipe can be used to place the concrete through the water.
During the concreting process, a crane should be used to handle the tremie pipe. Both the crane and the concrete pump should be set up in a convenient position to avoid movement during the pouring process. The tremie pipe can be used to displace water or bentonite slurry in the borehole, which can help to improve the stability of the pile borehole.
To avoid mixing concrete with the slurry in the borehole, 1/4 kg of granulated vermiculite can be poured into the tremie pipe before adding the concrete. The concrete should be placed continuously to avoid disruption, and the end of the tremie pipe should remain in the concrete for a minimum of 1m.
During the concreting process, the tremie pipe should be moved up and down using the crane or other suitable machines. Any sections that come out of the pile borehole should be removed, and the tremie pipe should be pulled out after the concrete reaches the top of the pile. Once the pouring process is complete, the temporary casing can be removed with necking and shearing of the poured concrete. Finally, the top part of the pile should be filled with concrete up to 15cm above the cut-off levels.
FAQs on concreting pile foundations
How do you pour a concrete pile?
When conducting pile borehole construction, if the borehole is found to be dry, then it is acceptable to use any appropriate method for pouring concrete. However, during the pouring process, it is important to ensure that the height from which the concrete falls does not exceed 2 meters. This will help to prevent the concrete from segregating and losing its homogeneity.
On the other hand, if the water table is high or slurry is being used to improve the stability of the borehole, then it is necessary to employ a tremie pipe to pour the concrete through the water. The tremie pipe is a specially designed pipe that is used to pump concrete into the borehole without allowing it to come into contact with the surrounding water or slurry. This method of pouring concrete helps to maintain the integrity of the pile borehole and ensures that the concrete sets correctly. By following these guidelines, pile borehole construction can be completed safely and effectively.
What is a concrete pile foundation?
A deep foundation is a type of foundation that is used to support the weight of a structure by drilling into a firm soil layer. These foundations are typically used in situations where the soil at the surface is not strong enough to support the weight of the superstructure.
To create a deep foundation, a hole is drilled deep into the ground until a firm soil layer is reached. This layer is then used as the base for the foundation, and the hole is filled with a material that will provide additional support, such as concrete or steel.
The advantage of using a deep foundation is that it allows the weight of the structure to be distributed over a larger area, reducing the amount of stress on any one point. This can help to prevent settling and other structural problems that can arise when the weight of a structure is not properly supported.
Overall, deep foundations are an important tool for engineers and architects when designing and constructing large structures. By providing a strong and stable base, they can help to ensure the safety and longevity of the building, even in challenging soil conditions.
Why are pile foundations used?
Pile foundations are a commonly employed solution to transmit the load of a structure from weak soil layers to stronger soil layers. This type of foundation is used when the soil at the ground surface is not sufficient to support the load of the structure. In such cases, piles are driven deep into the ground until they reach a more solid layer of soil, which can bear the weight of the structure without settling or shifting.
The piles can be made of various materials such as timber, steel, or concrete, depending on the load capacity required for the structure. The piles are designed to resist both the compressive and tensile forces that may act on them. The foundation system is comprised of a group of piles that work collectively to provide support to the structure.
The load capacity of the piles is determined based on several factors, such as the soil type, depth of the weak soil layer, the weight of the structure, and the anticipated loads. Proper design and installation of pile foundations are critical to ensure the stability and safety of the structure. Pile foundations can be used for a wide range of structures, including buildings, bridges, and offshore structures.
What is a tremie pipe?
A tremie pipe is a waterproof pipe specifically designed for pouring concrete underwater. It features a conical hopper attached to its upper end, which makes it easier to pour the concrete smoothly. The tremie pipe is an essential tool in underwater concreting, as it allows for the placement of concrete in areas that are submerged in water. It is typically made of steel or plastic, and it is long enough to reach the desired depth. By using a tremie pipe, the concrete is placed directly where it is needed, without allowing any water to mix in, ensuring a high-quality concrete structure. Tremie pipes are commonly used in marine construction, such as the building of ports, harbors, and bridges. They are also used in repairing and strengthening underwater structures.