Project

Keller and GEO-Instruments were on site together again on a small but technically challenging project in a prime location in central London.

London Pile rig control surveyor
Rig alignment was checked continuously throughout drilling

The project is a major redevelopment of a central London property, involving significant works undertaken on the interior and basement.
A relatively rare example of an indoor piling project, Keller were installing a single pile into the ground below the basement. The pile will support the base of a new lift to be installed into the property as part of the redevelopment.
The specification required a high degree of accuracy for the pile installation. At 600mm in diameter and a 25 metre depth, maintaining verticality of the pile was the a key priority.

GEO-Instruments’ specialist site engineering team worked with Keller throughout the process, using engineering surveying and borehole surveying techniques to ensure the pile stayed within tolerance.
Engineers employed drilling rig control monitoring and carried out regular borehole surveys during the drilling process in order to closely monitor vertical accuracy.

Control points were established on the drilling rig and continuously monitored using a Leica ICR70 Robotic Total Station throughout the course of drilling. This allowed the team to detect and correct any deviations caused by rig movements, ensuring the rig remained in the correct position.
In addition to the targets on the rig, real-time checks of the auger alignment were made throughout the drilling process. Measurements were taken reflectorlessly using the Total Station.
 

london pile rig control team
The works had to be carefully managed on a small, indoor work site

After every 2 meters drilled, the position of the borehole was determined using a DeviGyro RG40 borehole survey tool. By analysing the coordinates, any movement can be tracked and the drilling process adjusted accordingly. This data from within the borehole is essential for achieving the highest level of precision and accuracy.

Working together, the Keller and GEO-Instruments teams achieved a deviation well within the specified verticality. 
Projects like this require excellent communication and teamwork to meet strict requirements. 
GEO-Instruments were able to draw on extensive experience and industry leading technology to deliver the high accuracy results we are known for.

Read more about our Site Engineering expertise