Skip to main content

Developments in bridge monitoring technology

Advances in bridge monitoring technology should help ensure structural safety Highly productive, Fugro Aperio's ground penetrating radar system offers accurate scanning of bridge condition Bridge engineers can now benefit from a new technology designed to pinpoint shallow targets, such as masonry fixings, reinforcement bars or delamination between thin layers. This uses the latest high resolution ground penetrating radar (GPR) antenna and has been developed by Cambridge-based Fugro Aperio in the UK. Operati
July 9, 2012 Read time: 3 mins
The Soundprint acoustic testing system is now being widely used to examine bridge cable integrity
RSS

Advances in bridge monitoring technology should help ensure structural safety

Bridge engineers can now benefit from a new technology designed to pinpoint shallow targets, such as masonry fixings, reinforcement bars or delamination between thin layers. This uses the latest high resolution ground penetrating radar (GPR) antenna and has been developed by Cambridge-based 2929 Fugro Aperio in the UK.

Operating at a higher frequency than comparable instruments, 2,600MHz in comparison to the 1,500MHz range of most competing systems, the new system offers major gains in non-destructive testing technologies. This new system is able to pinpoint detail, such as multiple layers of reinforcement in walls and cracks in floors. According to Fugro Aperio, the technology offers powerful new capabilities in asset surveying for a range of highways applications, including assessment of post-tensioned bridges, bridge and tunnel decks, tunnel walls and pavements. As well as recording thickness to a depth of around 1m, the system can detect voids within and behind concrete, as well as delamination in concrete and asphalt. It also provides precise mapping of reinforcement and other embedded features, such as post-tensioning ducts and cables.

The package is highly portable as it is compact, rugged and is also suited for use where access would be difficult for conventional investigation methods. The system can be mounted on a trailer or vehicle to scan larger areas such as bridge decks, and for pavement evaluation and can survey 3-5 linear km of data/day. As well as concrete, this GPR capability is also effective on masonry, for the evaluation of brick arches, for instance, to determine thickness or to map ring separation and moisture.

Meanwhile Pure Technologies has developed the SoundPrint Technology, an acoustic monitoring system that is designed to detect the fracture of high-tensile steel wires such as those found in post-tensioned bridges and structures. The system uses surface-mounted acoustic sensors to detect the energy released by the fracture of a wire and locate the position of the break. The package is non-destructive, provides continuous monitoring to the structure and can make huge savings for bridge owners in unnecessary repairs and premature decommissioning.

When a high-tensile steel wire fractures, potential energy is released, causing the surrounding concrete to vibrate. This is detected by an array of piezoelectric sensors fitted to the structure and signals are then carried to a data acquisition system (DAQ) through a SoundPrint Smart Junction (SSJ) box. When signals reach the DAQ they are amplified and run through a series of filters and pre-processors, rejecting construction noise and traffic. Data passing through these primary filters is sent to a data processing centre through the Internet and software analyses the information to determine the time and location of a wire break. All this retrieved data can be viewed through a website.

The system can identify issues such as corrosion of steel tendons in post-tensioned bridges as this can cause them to fracture, compromising the strength and integrity of a structure. Conventional monitoring methods are time-consuming, expensive and may cause traffic delays. An alternative is the use of SoundPrint monitoring, which can be applied to structures where further deterioration can be tolerated.

Demand for the system has increased in the UK in recent years and, as authorised distributors of the system, the Transport Research Laboratory (777 TRL) is involved in the installation, commissioning and monitoring of the system on several structures. Recent installations include; Bowdon View Bridge on the M56 motorway at Junction 7 and the Thorley Lane Bridge on the M56 at Junction 5, near Manchester Airport.
RSS

For more information on companies in this article

Related Content

  • Proper GPR Surveying Techniques
    May 10, 2019
    A sustainably good road surface often depends on how well understood is the ground underneath the road’s route. Brian Jones* offers some best practice and advice for getting the most from ground-penetrating radar investigations Ground-penetrating radar (GPR) is one of the most accurate non-destructive testing (NDT) methods available. To get the most from GPR surveying, it is absolutely essential to understand how GPR tools work and follow best practices when conducting surveys. Key areas to be aware o
  • Fugro Aperio stage 12th DIPA conference in Birmingham, England
    July 16, 2012
    The 12th Developments in Pavement Assessment (DIPA) conference organised by Fugro Aperio was taking place today in Birmingham, central England. DIPA is Britain’s only highways event dedicated to pavement assessment, covering the latest policy, best practice and survey technology developments. Speakers include pavement experts from local government, consultancy and research, and the data collection sector.
  • Invisible detection
    February 6, 2012
    A self-contained, ground penetrating radar system (GPR) is now available from US Radar. The system is said to be technologically-advanced and simple to use, with a touch screen operating system and a variety of antenna frequency options. The Seeker GPR can be used in numerous surface materials such as soil, clay, concrete and brick. It integrates a complete imaging system into a single unit and can be used in application such as underground construction, road and bridge building, structural and civil engine
  • New concrete testing technologies improve speed, safety and quality
    July 8, 2016
    Developments in data processing and management are revolutionising the way concrete strengths can be measured and used to improve efficiencies - Kristina Smith reports on two new technologies A new system that uses thermal imaging to measure the strength of sprayed concrete tunnel linings is being trialled for the first time in London. The brainchild of Dr Benoit Jones, managing director of Inbye Engineering, the technique could lead to improvements in safety, quality and – in the longer run – productivi