Making the underworld visible

This post was originally published on the ESPRC blog.

Not knowing the exact location of gas and water pipelines, electricity cables and sewage outlets can result in excavations in the wrong place and cause serious disruption to both utilities supplies and above ground transport. Researchers at the University of Birmingham are working on ways of identifying more accurately what is below the ground, saving time and money.

Knowing where gas and water pipelines, electricity cables and sewage outlets are located is not always easy. Most are carried underground, and some are over two centuries old. The fact that many sit below surface transport routes such as roads, pedestrian areas or railways can mean that maintaining, replacing or installing these can cause serious disruption to both utilities supplies and above ground transport.

Not knowing their exact location can result in excavations in the wrong place which can add to congestion and delays. There is a symbiotic relationship between the surface infrastructure, the ground on which it rests and conduits which lie beneath it: intervene physically in one and the others are almost inevitably affected in some way, either immediately or in the future.

Along with my colleagues, in the Department of Civil Engineering at the University of Birmingham’s School of Engineering, we are working on many of these infrastructure challenges. We are:

• Developing a highly-sensitive quantum technology-based gravity gradient sensor to map deeper underground space. This determines the gravitational field of the subsurface by measuring density variations. Sensor and environmental noise and location effects affect existing sensors. The new sensor suppresses some of this noise and thus is able to detect smaller objects at increased depth.
• Creating an integrated streetworks assessment framework encompassing transport and buried utility infrastructures, and the ground that supports both, thereby providing a methodology to assess the impact (both short- and long-term) of any intervention with respect to the transport and buried infrastructure from a holistic, sustainability viewpoint.
• Developing surface-mounted and in-pipe multi-sensor technologies for utility mapping and condition evaluation to provide better information to utility companies and engineers prior to any work conducted. This leads to a reduction in the number of holes dug in the wrong place and reduces the risk of damaging buried assets with the associated health and safety implications and increased costs.
• Developing deterioration models for ageing infrastructures to help engineers and (local) government to assess the remaining life of our infrastructure to maximize its life and intervene at the most appropriate time during the deterioration cycle.
• Researching robots to carry out routine streetworks operations thereby providing alternative solutions to high risk or repetitive jobs.
• Exploring the value realised from infrastructures and novel business models, thereby providing a justification for investment and alternative ways of funding future infrastructure projects.
• Researching opportunities to exploit underground space for city sustainability and resilience. With increasing sizes and densities of population in cities, surface space will become limited and thus we are exploring ways to utilise the underground space in many different ways.
• Researching and developing reliable, cheap and easily installed relative measurement sensors for utility network condition monitoring, for example wireless sensor networks for water pipes (Smart Pipes).
• Constructing the National Buried Infrastructure Facility as part of the UK Collaboratorium for Research in Infrastructure and Cities, which will be the largest of its kind to carry out research and training in the detection of buried assets, their condition assessment, soil-structure interaction of buried utilities, geo-structures, tunnelling, trenchless technologies for the installation and renewal of buried assets, to name but a few.
• Assessing the impact of pressure waves on tunnels and tunnel portals, focussing especially on high speed trains using our TRAINRig.

If any of the above is of interest, please contact me at n.metje@bham.ac.uk.