Tue, 10 November, 2020
TWI is part of a collaborative project to develop a ground penetrating radar (GPR) capable of automatically inspecting dam structures and creating a map of the internal structure for fault detection and analysis.
The Philippines-based project is being undertaken alongside drone/UAV NDT inspection development company Autonomous Devices Ltd, and Filipino power sector procurement company Quantum Leap JMB Marketing (QLM).
As the project nears completion, we took some time to speak with TWI’s non-destructive testing project leader Giorgia Ercolini about the objectives and benefits of DamGPR.
Giorgia Ercolini
Firstly, what will DamGPR deliver to the marketplace?
The project aim is to conduct a feasibility study to develop a proof of concept for a Ground Penetrating Radar (GPR) capable drone for dam inspections. Dams have a long life-expectancy, however, they are susceptible to degradation that can start as minor problems and be present for years. Current inspection methods, in the Philippines, are regular visual inspections that can only detect problems when they have developed to a critical state. DamGPR-Drone will provide a method for the early detection of defects, thus allowing for preventative maintenance, reducing the cost of repairing and up-keeping dams. There is also potential for DamGPR-Drone to expand beyond dams and reservoirs to other similar infrastructure, including railway embankments, canal infrastructure, nuclear power plants, and highway embankments and tunnels.
What are the benefits of using a drone over traditional inspection methods?
Current condition monitoring technology involves human interaction with physical equipment on the ground, or embedding wireless sensors in structures, which can be labour intensive and potentially dangerous. Drones can be used for visual inspection and identification of surface cracks/defects using infrared thermography sensors. The disadvantage of visual inspection is that it does not provide information about the properties or internal condition of the concrete.
The usage of a drone with integrated GPR system will move inspections from dangerous manual inspection via rope/crane/scaffolding access to a secure, remote inspection method. This will make the inspection of dams a more attractive option for female inspectors, as the job will be less physically demanding and less dangerous. Policy makers will benefit from having an inspection method that is safer, faster and cheaper to implement than current methods, allowing them to mandate for more regular inspections of dam structures.
What were the main challenges with this project and how did you overcome them?
The integration of NDT techniques with drones has been hindered by the weight and design of the NDT inspection equipment and by the need for drones to be in contact with or close to the surface being inspected. In order to develop our proof of concept, key contribution to overcome the challenges was given by the multidisciplinary partners’ skills: Autonomous Devices are developing autonomous hybrid driving and flying systems for remote inspection; QLM is a procurement and service company in the power sector from the Philippines in conjunction with the Government of the Philippines; TWI are experts in NDT technology and have extensive experience in GPR development and adaptation. Moreover, a continuous interaction between partners and dams’ operators, initially delayed by Covid-19 restrictions, has allowed us to identify the key points to satisfy requirements and end users’ specifications.
How about the environmental and health benefits associated with this project?
Developing an inspection solution for dams that will lower the inspection and maintenance cost will, over time, lead to an increase in dam development and a decrease in coal power generation, leading to reduced air pollution, benefitting the health of the local people and the environment.
Moreover, current inspection methods include rope, scaffolding and crane access. DamGPR-Drone removes this need for manual inspection and replaces it with a remote inspection solution, increasing the safety for personnel.