Aberdeen harbour expansion

THE BRIEF

The Aberdeen Harbour Expansion Project involves the development of a new harbour in Nigg Bay, Scotland. The project consists of accropode breakwaters and a harbour basin with more than 1km of berthing line.  Berthing quays are formed by a piled suspended deck structure and reinforced concrete caisson structures. Robert West elaborated the Basis of Design document and undertook an extensive sensitivity study for selection of the concrete caissons granular bed layer and backfill to caissons. To achieve stability, several caisson geometries were analysed that included variation of caisson cell geometry and toe lengths together with floatation stability for caisson transport from Northern Spain to Aberdeen. Total reinforcement quantities were also derived based on the different earth fills and geometries considered. Robert West performed these services in collaboration with Proes, a Madrid based engineering company. 

VALUE-ADDED SOLUTION

The work developed allowed the evaluation of the performance during transport and installation of the caisson thus allowing the Contractor to select adequately planned resources. Robert West supported the Client maximising the use of the dredged material as cell and back fill by implementing a shear key solution. The analysis carried out by Robert West and Proes allowed discarding several geometries due to low stability values and provide reinforcement estimates within a 3% accuracy before advancing to detail design.

FINAL OUTCOMES

Seven final caisson geometries were selected to be developed for detail design and Robert West, with Proes, produced the detail calculations and drawings to be taken for construction stage.