The Design, Installation – Monitoring of High Capacity Antiflotation Bar Anchors to Restrain Deep Basements in Dublin

The construction boom in Dublin over the past decade has resulted in a demand for larger and deeper basements. These structures often extend several metres below the local ground water level and may have insufficient dead load to resist flotation.

This paper discusses four recent case histories where passive high capacity bar anchors, often-referred to as Anti-flotation Tension Minipiles (ATMs), provide the necessary restraint against hydrostatic uplift. In particular, it discusses opportunities where close coordination of the ATM designer and the basement slab designer can provide the optimum solution, both from a cost and programme perspective.

Due to the competent founding strata in much of Dublin, either the boulder clays, dense gravels or limestone bedrock, the use of ATMs is commercially attractive and offers several advantages over traditional stressed tendon anchors.

This paper concludes that full understanding of the appropriate design case and close interaction between the structural, geotechnical and ATM engineers is necessary to achieve the optimum basement solution.

• Introduction

• Typical Dublin Ground Conditions

• Design Philosophy

• Smithfield, Dublin

• Spencer Dock, Dublin

• Elm Park & Swords, Dublin

• Conclusions

• Acknowledgements

• References