Ready mixed concrete for bored pile

[PAN]

The contractor advise me that ready mixed concrete must be used for bored pile work.

Are there any reference standards to reject concrete mixing at site for bored pile work? Please comment.

 

[cm3]

You definitely have to use ready mix concrete to ensure continuous concrete delivery to complete your concreting work within an hour. You have to ensure that the bore holes dont cave-in (use bentonite/polymer) using sounding. Ensure that additional 10% cement on mix is added to compensate for the loss during use of tremie pipe. Check the slump and ensure it is not below 180mm. 200 mm is ideal for this activity (SCC Mix). If you have anymore querries, please make contact.

 

[Zambo]

cm3,

the question about readymixed concrete is not phrased in a way which allows for a definite answer. The fact is that properly batched concrete is necessary, whether this is achieved by the contractor by using his own on-site batching plant or by using an off-site readymixed concrete supplier is his choice.

There is no spcific requirement for an additional 10% cement for a tremie concrete mix. Many large piling projects now use pumps and a mortar mix is used first, this mortar is of course discharged away from the pile.

Bentonite or polymer (or a mix of the two) will often be used as excavation support. Depending on the specification the pile may typically have to be completed within 12-24 hours of excavation. The actual time for placing the concrete will vary according to the size and depth of the pile, 100m+ is not unusual.