FONDEDILE FOUNDATIONS has just been awarded the contract to install piles for the A90 Crammond Bridge strengthening scheme for the City of Edinburgh.
Work, due to start this month with a precontract trial piling programme, forms part of the upgrading of the bridge deck from its 25t weight limit to meet European load standards.
The bridge carries the main road across the River Almond and is in a conservation area.
Designed by consultant Carl Bro Group, the scheme involves providing additional support for the bridge by constructing two new piers and a portal frame, which will reduce the deck spans and increase its load-carrying capacity.
Initially the plan called for 600mm diameter vertical piles to carry the new piers and frame but Fondedile, along with main contractor Miller Group, proposed using its Pali Radice minipile system.
The minipile uses between 76mm and 280mm diameter cast insitu bored piles.When used in underpinning, piles are formed through the structure, providing a direct connection between the foundation and competent ground, forming 'roots', hence its name (Italian for root piles).
It is also suitable for installing new foundations with difficult ground conditions and/or restricted access.
For this contract, raking 200mm diameter piles will be installed to directly resist vertical and horizontal bending moments, predominately in axial compression, and will reduce the number of piles needed.
Design was verified by Fondedile's computer-based pile group analysis software as well as an independent checker.