Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
CGL was appointed by Telford Homes to undertake an analysis to establish the potential impact of the proposed development on two Docklands Light Railway (DLR) tunnels that run directly below the site and beneath the footprint of the development.
The redevelopment at Calder's Wharf, Isle of Dogs is a four-storey building consisting of 21 residential units and is bounded to the south by the River Thames. A previous proposal, submitted by others, recommended an expensive bored pile foundation system, this was not a viable option for the Client and showed a risk to the tunnels with large diameter rotary bored piles required.
CGL and Walsh, the structural engineers developed a compensated raft foundation for the development, to remove the requirement for piles, and to mitigate the risks to the underlying tunnels. A three-metre deep 'basement' was dug below the proposed development and filled with polystyrene blocks, the removal of soil compensated for the weight of the building giving rise to no net change in stress on the tunnel linings. This solution made the project viable for the Client.
A PLAXIS 3D Finite Element model was used to run a series of steps to demonstrate the viability of the scheme to DLR and to determine ground movements caused by the proposed construction. The model was used to generate the stress history on the tunnels and to assess the impacts both during the short term and over the long-term as the 'basement' was excavated and the structural loads were applied.
The analysis facilitated a complex negotiation with DLR and their supervising engineers, enabling the development to be constructed with no piled foundations, providing a considerable cost and programme saving to the client.
Calder’s Wharf, Isle of Dogs, London
[email protected] cgl-uk.com
PLAXIS 3D Finite Element Modelling and Analysis
Client
Telford Homes
Structural Engineer
Walsh
Services
Ÿ Review of Existing Site InvestigationŸ PLAXIS 3D Finite AnalysisŸ DLR Impact Assessment
Godalming London Exeter
01483 310600 020 3096 7567 01392 439905
Harrogate Bristol Dublin01423 276000 0117 373 6140 (01) 554 6210
Hoop Forces (final)
Development Plan
Tunnel Displacements (final condition)