Bedford Riverside

Pile Type: CFA

Number of Piles: ???no.         

Diameter: 600mm-  900mm

Depth: 8.0m

The ground conditions predominantly consisted of made ground overlying Alluvium into the granular deposits of the felersham member. Limestone bedrock of the Great Oolite Group was encountered at 4.0m below ground level. 

A rock socket design was proposed into the limestone after a series of trial bores and extensive site investigation on site. Piles were designed to be a maximum of 8.0m in depth, however it was the high loads from tension/shear and eccentric moments which proved as challenging as the 4000kN individual pile loads. 

Franki Foundations worked closely with the client and the project consulting engineer to develop a piles solution which met the requirements of the project, while being executable with the preferred CFA pile installation method, this was critical to the client who wanted to avoid using a rotary bored method due to tight programme constraints. Pile diameters ranged from 600mm diameters to 900mm diameter and were installed with a Soilmex R625 piling rig for the increased pulldown force required to "bite" into the limestone and achieve up to 5m rock sockets.