Smart Foundations with Distributed Fibre Optics Technology
Lead Research Organisation:
University of Cambridge
Department Name: Engineering
Abstract
Design limits are frequently based on strain developing in the structure. Although strain measurement is well established, current practice has until recently been restricted to measurement of point-wise strains by means of vibrating wire (VWSG) or metal foil strain gauges and more recently by fibre optics utilising Fibre Bragg Grating (FBG) technology. Where structures interact with soil, (e.g. underground infrastructure such as foundations, tunnels or pipelines) or indeed in the case of a soil structure (road or dam embankments), the state of the structure is not fully understood unless the complete in situ strain regime is known. In the context of monitoring strain in piled foundations, tunnels, pipelines, slopes or embankments, capturing the continuous strain profile is often invaluable to pinpoint localised problem areas such as joint rotations, deformations and non-uniformly distributed soil-structure interaction loads. In this project, we propose to use a unique fibre optics technology called the 'Brillouin optical time-domain reflectometer (BOTDR)'. The novel aspect of this new technology lies in the fact that tens of kilometres of fibre can be sensed at once for continuous distributed strain measurement, providing relatively cheap but highly effective monitoring systems. The system utilizes standard low cost fibre optics (potentially 0.1/m) and the strain resolution can go down to 2 micro strains. We will demonstrate the importance of distributed strain measurements to monitor the performance of building foundations at field sites in the UK and US. Using the distributed strain data, a design tool that optimises the performance of foundations that require rehabilitation, repair and reuse will be developed with industrial collaborators. The project has supports from UK Industrial partners as well US collaborators (National Science Foundation and Northwestern University).
Organisations
- University of Cambridge, United Kingdom (Lead Research Organisation)
- Arup Group Ltd, United Kingdom (Collaboration, Project Partner)
- Whitby Bird and Partners, United Kingdom (Collaboration, Project Partner)
- Skanska UK Ltd, United Kingdom (Collaboration)
- Geotechnical Consulting Group Ltd, United Kingdom (Collaboration, Project Partner)
- Northwestern University, United States (Project Partner)
- National Science Foundation, United States (Project Partner)
- Cementation Foundations Skanska Ltd, United Kingdom (Project Partner)
Publications

Bourne-Webb P
(2009)
Energy pile test at Lambeth College, London: geotechnical and thermodynamic aspects of pile response to heat cycles
in Géotechnique

Leung Y
(2010)
Role of Linear Elasticity in Pile Group Analysis and Load Test Interpretation
in Journal of Geotechnical and Geoenvironmental Engineering

Leung Y
(2010)
Theoretical Study on Pile Length Optimization of Pile Groups and Piled Rafts
in Journal of Geotechnical and Geoenvironmental Engineering

MOHAMAD H
(2010)
Behaviour of an old masonry tunnel due to tunnelling-induced ground settlement
in Géotechnique

Mohamad H
(2012)
Monitoring Twin Tunnel Interaction Using Distributed Optical Fiber Strain Measurements
in Journal of Geotechnical and Geoenvironmental Engineering
Description | Cementation Foundations Skanska Ltd |
Organisation | Skanska UK Ltd |
Department | Cementation Skanska |
Country | United Kingdom |
Sector | Private |
Start Year | 2006 |
Description | Geotechnical Consulting Group Ltd |
Organisation | Geotechnical Consulting Group |
Country | United Kingdom |
Sector | Private |
Start Year | 2006 |
Description | Ove Arup Ltd |
Organisation | Arup Group |
Country | United Kingdom |
Sector | Private |
Start Year | 2006 |
Description | Whitby Bird and Partners |
Organisation | Whitby Bird and Partners |
Country | United Kingdom |
Sector | Private |
Start Year | 2006 |