Location: Vidin, Bulgaria
Client: FCC Construction
Project Value: €282 million
AGL Consulting were specialist geotechnical consultants to the Contractor – FCC Construction – on the design and testing of the pile foundations for the main bridge piers of a 1.4 km long multi-modal road and rail cable-stayed bridge over the River Danube between Bulgaria and Romania.
We carried out a peer review of the pile group design to advise on the pile spacing, pile group capacity and settlement in a technical mediation role to obtain approval for the pile designs. The foundations were made up of 24 No. 2.0 m diameter bored piles arranged in a 3 x 8 group. The piles were up to 60 m long and were constructed through granular alluvium and overconsolidated cohesive Pleistocene deposits.
We interpreted the results of the initial pile load tests, which were carried out using Osterberg Load Cells, and advised on construction techniques and monitoring methods for improving the base and shaft capacity of the piles.
We also carried out an independent assessment of the stiffness matrix used to analyse the performance of the piles under lateral loading.