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Grout settlement is a normal part of an Auger Cast in Place Grouted Pile installation in some soil conditions. Once an Auger Cast in Place Grouted Pile is constructed, while the grout is still fluid, the pressure of the grout column can cause the soil surrounding the pile to compress. This process is observed by the lowering of the grout level at the top of the pile. Fresh grout can be added to the top of the pile (topping off the pile) as long as the grout in the pile is still fluid and no contamination is occurring at the top of the pile.

Reinforcing, when required, can be installed while the cement grout is still fluid or if necessary (in the case of full length single reinforcing bars), through the hollow shaft of the auger prior to the auger withdrawal and grouting process. If the reinforcing is installed after the pile is grouted centralizers are used to maintain the required clearances.

Per the 2009 IBC 1810.3.9.2 No reinforcing is required except where subject to uplift or where required due to the moment strength determined using the load combinations of Section 1810.3.9.1. Cage reinforcing is used to carry lateral or seismic loads in the upper portion of the pile typically the top 15 to 20 feet. Rather than using the cage to carry uplift loads it is typically more economical to use a center bar in the pile to carry the uplift loads. The longer the pile, the more difficult and expensive the installation of a full length cage becomes.

The most typical grout strengths for Auger Cast in Place Grouted Piles range from 3000 psi to 5000 psi. 6000 psi grout is becoming more common and has been used consistently in several locations. Higher grout strengths such as 7000 psi can be used in some locations, however special attention must be paid to curing of grout specimens especially prior to them being delivered to the controlled environment at the test laboratory.