Protecting our lighthouses for the safety of mariners – Stormlamp – full length film

STORMLAMP – STructural behaviour Of Rock Mounted Lighthouses At the Mercy of imPulsive waves – is an EPSRC funded collaborative research project between the Universities of Plymouth, Exeter and University College London and a number of industry partners. 

The project characterises wave loading and structural performance of rock lighthouses, using combined field measurements, laboratory studies and analytical and numerical investigations, with the aim of supporting management of lighthouse structural conditions.

To find out more, check out the video below, created by Filmbright http://www.filmbright.com/

For more information about STORMLAMP, visit https://stormlamp.org.uk/

VSimulators – virtual reality facilities to support human factors research and innovation

Bridge with Users

Plans for a major new centre for research and development in the vibration engineering sector are in the final stages of development at the Universities of Exeter and Bath. In Exeter, a new, purpose built facility featuring a state-of-the-art VSimulator will, for the first-time, link structural movement and environmental conditions, with human perception monitoring, psychology and physiology, within a fully controllable virtual environment. At Bath, the VSimulator facility will focus on sensory perception of external environment and surroundings, and feature controls over room lighting colour and intensity, temperature, humidity, noise, air quality, and scent. The Bath facility will focus primarily aimed at exploring motion in tall buildings. The facilities will offer the opportunity to analyse the human factor impact of environments, whilst enabling full data capture.

VSimulators at the University of Exeter will be located on Exeter Science Park and will open in 2019. Meanwhile, the VSimulator at the University of Bath will be open from the end of 2018. The initial environments being studied in this EPSRC funded project include walking across bridges, working in high-rise office blocks and dancing in a crowded stadium. The VSimulators will recreate the impact of subtle motion in these spaces to enable a better understanding as to how this could affect the wellbeing of people, their work performance or behaviour.

Stadium With Users
The Exeter VSimulator scenes are being created by ‘Experience Designers’, Holovis, who specialise in multisensory training and simulated environments, with development of emerging technologies in these spaces. Virtual Reality will provide the ability to deeply immerse people into the desired scenarios, with up to nine people able to participate simultaneously.

The 4×4 metre space is on a custom designed Hexapod motion platform with freedom of movement in six directions. It was designed by E2M Technologies in Amsterdam, creating a fully instrumented floor capable of data capture and analysis. People can move freely around this space, seeing avatars of the other participants in the virtual world, tracked to their unique perspective. Alternatively, the space could recreate an existing environment, with physical objects placed where a virtual equivalent would be located. In these ways, the facilities are capable of being customised to fully explore the sensory immersion and human factor responses.

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Each person’s movements and reactions are captured via full body monitoring, and it is these metrics that will help the team to devise solutions to mitigate impact and assist designers, planners, architects and engineers in the future construction or refurbishment of buildings. However, there are uses beyond the construction and civil engineering field, with interest being expressed by the medical community, biomechanics specialists, the entertainment industry, sports scientists, psychologists, marine, autonomous vehicle, data science and virtual reality developers, amongst others.

Image of Exeter Science Park

Dave Elliott, Business Development Manager at Holovis comments:
“Increasingly, people are living and working in innovative environments where very little is known about the impact of the vibrations or their environment. The highly realistic nature of this multisensory environment will give them a true sense of immersion, making them believe they are in that location. Therefore they will subconsciously react to stimuli as they would in the real world. The flexibility of the VSimulators allows for an incredible range of conditions to be simulated, which will really help to advance the research and innovation in many sectors.”

Julie Lewis-Thompson, Commercial Manager for the VSimulators Project explains:
“There are extensive and diverse areas of commercial and academic interest for the VSimulators research facilities. We have identified 38 industry areas for exploration with interest from an expanding global based clients list, both within industry and academia..”

“There are multiple opportunities for interdisciplinary research including architecture for wellbeing, computer science, data analytics, the built environment, construction design and human factor responses. These facilities will place the Universities of Exeter and Bath at the forefront of expertise in the use of virtual reality within industry focused research”

For VSimulators at University of Exeter and University of Bath please contact
Julie Lewis-Thompson, T: +44 (0)1392 722603, E: j.a.b.lewis-thompson@exeter.ac.uk

For the Vibration Engineering Section please contact Katy Manning, T: +44 (0)1392 725821, E: k.l.manning@exeter.ac.uk

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Students from all over the UK attend structural vibrations summer school run by VES

Participants from academia and industry from all over the UK attended a week long structural vibrations residential summer school run by the Vibration Engineering Section (VES) and partners from the University of Liverpool, at the University of Exeter.

Funded by the Engineering and Physical Sciences Research Council (EPSRC) BAYOMALAW grant the school attracted undergraduate and PHD students from University College London the Universities of Exeter, Oxford, Liverpool, Aberdeen and Warwick, as well as an industry visitor from WSP Parsons Brinckerhoff.

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The course covered structures with single and multi-degrees of freedom, stochastic process and stochastic structural dynamics, power spectral density estimation, vibration testing and experimental modal analysis.

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As well as theoretical sessions, students carried out experimental modal analysis in the state of the art structures lab at the University of Exeter, which prepared them for a modal test of Baker Bridge at Sandy Park.

Bridge test 2Bridge test 1Bridge test 3Bridge test 4

Emma Hudson, Senior Consultant at Full Scale Dynamics Ltd, gave an industry talk to the group, presenting examples on her experimental work on structures such as sports stadia and lighthouses, as well as her work with ground borne vibrations.

The summer school culminated in group work, which took place in the Structures Lab.
James Brownjohn, who ran the school alongside Ivan Au from the University of Liverpool, said:

“With the increasing use lighter weight, more flexible materials in structures leading to more vibrations, which could be problematic in terms of safety and human perception and comfort, the ability to test and control such vibrations is becoming all the more crucial a skill for the structural engineers of the future.

“We would like to thank the EPSRC, whose funding has enabled us to run this course, which will have given the participants both an important theoretical grounding, and some practical experience in how to carry out these important tests.”

Engineers of the future present their projects to industry experts

Engineering students at the University of Exeter presented on a range of innovative projects including drones, a self-propelled capsule, a knee brace and a shaking table to industry experts at a special event.

More than 100 Master of Engineering (MEng) students from across a range of disciplines showcased their group work as posters, displays and presentations, to representatives from Babcock, the Institution of Mechanical Engineers, the Royal Devon & Exeter Hospital, Exeter College, and BSW Consulting Engineers.

The day-long event, which took place at the University’s Streatham campus, was an opportunity for students to showcase their project work and to network with industry contacts.

Professor James Brownjohn, lead academic for the module, said: “This cohort of students have created some really impressive work, and this experience will have sharpened crucial skills required by industry, such as team working, problem solving and project management.

He added: “The poster day also provides an excellent opportunity for representatives from industry to meet and engage with the engineers of the future.”

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The Natural Ventilation team with their project and poster

 

VES experts to run CPD course in Vibration Serviceability in June 2018

Engineers interested in fundamental vibration theory can enrol on IStructE’s CPD course run in London by our experts. To find out more about the event on 13th June 2018, visit

There is a second day of the course, covering the applications of vibration engineering, on 14th June 2018 and a discount for booking on both days. To find out more, visit https://bit.ly/2q8js0M

Check out recent testimonials about the course below:

Very good course overall. Based on the courses I have attended over the years, the speakers are the key to making the course successful or not. The combination of lecturing professors that also practice on a commercial basis was a huge benefit.

 A big thanks to the 2 presenters. Very knowledgeable people. Good presentation skills.

 Fantastic speakers, well presented course, both very personable and helpful. Thank you.

To find out more about the expertise of the professors running the course, visit Alex Pavic’s page on the VES website here and Paul Reynolds’ page on the VES website here

 

 

New paper published: Using inertial measurement units to identify medio-lateral ground reaction forces due to walking and swaying

Using inertial measurement units to identify medio-lateral ground reaction forces due to walking and swaying is now published in the Journal of Sound and Vibration.

Measurement of walking ground reaction forces (GRFs) in-situ is vital for understanding the mechanisms of human loading, including feedback effects such as observed in the London Millennium Bridge, but it is impossible to recover GRFs directly.  Following successful identification of vertical GRFs using inertial measurement units (IMUs) the technique was adapted to measure lateral components, which is a much greater challenge due to imperfect IMU azimuth identification and personal sway characteristics in human gait.

The methodology was also used to identify lateral GRFs due to on-the-spot swaying, which turns out to be a powerful approach for forced vibration of massive low frequency structures (such as tall buildings), since a single person can generate over 400 N harmonic lateral force.

A bi-product of the research is identification of ‘dynamic load factors’ for lateral GRFs, providing much better definition than decades-old guidance which underestimate them to a significant degree.

Structural Testing of a Heritage Railway Bridge with the Flying Scotsman Locomotive

A team of researchers from the Vibration Engineering Section returned to the Mineral Line Bridge in Somerset, to monitor the deflections of the bridge under different loading conditions. The bridge forms part of the West Somerset Railway (WSR), a heritage railway line with 20 miles of track in the South West of England.

The team, consisting of Farhad Huseynov, Yan Xu and Karen Faulkner, also formed part of the research group which had previously gathered strain data and rotation data of the bridge under train loading conditions.

The purpose of repeating the test was to analyse the performance of the bridge under loading from the Flying Scotsman engine.  The Flying Scotsman, one of the most well-known steam engines, was constructed in 1923 and was the first steam engine to officially record a speed of over 100 mph.

To achieve this speed, the engine itself measures 21.3 m in length and weighs 97.8 tonnes. This is significantly larger than the Raveningham Hall engine, and, with a length of 19.2 m and a weight of 76.4 tonnes, is the largest train belonging to the WSR. The aim of the testing was to measure deformations of the bridge under loading from the passing trains and to determine the effect of the larger Flying Scotsman locomotive on the bridge.

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Flying Scotsman Locomotive passes over the Mineral Line Bridge

The Mineral Line Bridge is located on the outskirts of Watchet and was originally constructed to carry the Minehead route over the West Somerset Mineral Railway. The Mineral Railway now operates as a footpath and cycle path open to the public. The bridge opened in 1862, has a single span of 14.8 m and is constructed skewed at an angle of 60° to the pathway beneath.

A series of accelerometers were installed on the bridge deck at five test points, measuring at each abutment and at quarter-span, mid-span and three-quarter-span. The angle of rotation of the bridge deck at each test point was inferred from the accelerometer data. This rotation data was then used to determine the deflection of the bridge.

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Accelerometers installed on the bridge

The Imetrum camera was used to measure deflections of the bridge under loading from the passing trains. Three Imetrum cameras were set up on tripods and targets were installed, one at mid-span on the bridge deck and two on the western abutment. The abutment deflection was monitored to gather information as part of a previous study, but the main focus of the testing on the day was to measure the deflection of the bridge at mid-span.

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Imetrum targets and cameras installed on the bridge

By comparing the results of the deflection calculated from the rotation data and measurements from the Imetrum camera, the team were able to verify the deflection measurements obtained from the accelerometers. There was good correlation between the two measurements, verifying the procedure used by the research team.

The results indicated increased deflections and rotations under loading from the Flying Scotsman, but was safely within the tolerances of the bridge.

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Raveningham Hall Locomotive passes over the Mineral Line Bridge

The weather conditions were not ideal on the day, with periods of rainfall intermixed with sunny periods throughout the day. This required the equipment to be covered with plastic bags for parts of the day, though this was found to have a negligible effect on the data.

To find out what happened when VES last tested on the bridge, look at the previous blog post Structural Testing of a Heritage Railway Bridge

Testing a simply supported bridge structure at Kyoto University

VES researcher Farhad Huseynov recently went to Japan to carry out experimental studies in collaboration with a research group at Kyoto University.

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Farhad Huseynov in Japan

The test, which aimed to validate a newly developed bridge condition assessment methodology was performed in the Structures Laboratory on a 5.6 metre long simply supported bridge structure at Kyoto University. Figure 1 shows the test structure.

Kyoto 1

Test structure

The test structure was stiffened at various locations by attaching steel plates on the girder flanges, and the response of the structure to a moving 4-axle vehicle was measured using QA-750 uniaxial accelerometers. Subsequently, a developed bridge condition assessment algorithm was applied to validate the robustness of the methodology.

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4-axle vehicle model
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QA-750 accelerometer installed at the bridge support location
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Stiffening plates attached at the bridge midspan location

The results obtained from the study prove that the developed methodology successfully identifies stiffening locations, and therefore is a promising tool for real bridge condition assessment applications. In the future, there are plans to use it to validate the procedure on a full-scale railway bridge structure.

 

New paper published on Bayesian operational modal analysis of Jiangyin Yangtze River Bridge

A paper about the testing and modal analysis of a Chinese long span suspension bridge has been published in the journal Mechanical System and Signal Processing. 

Bayesian operational modal analysis of Jiangyin Yangtze River Bridge is a result of the EPSRC project BAYOMALAW, led by Prof. Ivan Au from Liverpool and Prof. James Brownjohn from VES. 

It is the first published account of modal testing of a Chinese bridge by a western team and is co-authored by staff from Jiangsu Yangtze Bridge Co and Jiangsu Transportation Institute.

The paper describes the novel instrumentation specifically developed for the project, that allows precision synchronisation of loggers not having access to wireless or GPS signals. The paper is the first example of test planning for optimised operational modal analysis, to obtain the most reliable modal parameters.