As pile foundations carry a lot of load, they must be installed with utmost care. The selection of suitable equipment and the process employed for concrete pouring may vary based on the pile size and location of the structure.
If the pile borehole is dry, one may use any suitable means to pour concrete, but the falling height of concrete should not exceed 2m. However, if the water table is high, or slurry is used to improve the stability of the borehole, then employ tremie pipes to pour concrete through water.
You can estimate concrete volume based on length, diameter, and the number of piles. Select pumping machinery based on the location of the building and the concrete quantity to be placed. Piles are reinforced concrete columns drilled deep into a firm soil layer to support the superstructure’s weight.
How to Pour Concrete for Pile Foundation?
- Begin concreting as soon as borehole drilling is completed.
- Clean the bottom of the borehole before the concreting process.
- The length, diameter, number, and location of piles determine the volume of concrete and the concrete pump that is best for the job.
- If the pile borehole is not dry, pump the concrete through a tremie pipe to place the concrete through the water, Fig. 1
- Use crane to handle the tremie pipe during concrete pouring, Fig. 2
- Set up cranes and the concrete pump in a convenient position at the construction site. Use a long hose to avoid movement of both the crane and the pump to pour concrete pile.
- The tremie pipe can displace water or bentonite slurry in the borehole, which can be used to improve the stability of pile borehole.
- Insert the tremie pipe section by section. Attach the required number of tremie pipe sections to reach the bottom of the pile and attach the top part, Fig. 3 and Fig. 4.
- If you want to avoid mixing concrete with the slurry in the borehole, pour 1/4 kg of granulated vermiculite in the tremie pipe before pouring concrete.
- Place concrete continuously and try your best to avoid disruption of concrete placement, Fig. 5.
- The end of the tremie pipe should be within concrete for a minimum of 1m.
- Pull up the tremie pipe as the concrete fills the pile borehole. Move the tremie pipe up and down during the concreting process with the help of the crane of any other suitable machines.
- Remove any sections that come out of the pile borehole.
- Pull out the tremie pipe after the concrete reaches the top of the pile.
- After that, remove the temporary casing with necking and shearing of the poured concrete.
- Finally, fill the top part of the pile with concrete up to 15cm above cut-off levels, Fig. 6.
FAQs on concreting pile foundations
If the pile borehole is dry, then use any suitable means to pour concrete, but the falling height of concrete should not exceed 2m. However, if the water table is height or slurry is used to improve the stability of the borehole, then employ a tremie pipe to pour concrete through the water.
It is a type of deep foundation drilled deep into a firm soil layer to support the weight of the superstructure.
Pile foundations are used to transfer loads of the structure through weak soil layers to a strong soil layer.
It is a waterproof pipe that is used to pour concrete underwater. A conical hopper is attached to its upper end to facilitate concrete pouring. Read more on tremie pipe and underwater concreting.