EngAnalysis were engaged with the challenge of designing a structural monitoring system that was to be installed during the construction of a 5 story steel framed building at a University campus.
Working with the University Engineering Faculty and closely with the construction company, EngAnalysis were able to install sensors on all floors from the ground floor up to the top floor. The intensive construction schedule with completion due before the start of 2020 Lectures required our team to grow and shrink with construction progression as the locations for sensor mounting become accessible.
Fire proofing materials present on all steel members presented us with a unique installation requirement of removal and reinstate of the materials after sensors were in-place and tested to confirm operation.
Sensors were positioned throughout the building to measure/detect movement of the structure and also the behaviour of the structure to climatic changes and internal loadings. The system contained the following sensor types:
- Accelerometers
- Full Bridge strain
- Quarter bridge strain
- Embedded concrete strain and temperature
- Vibrating wire strain
57 pairs of accelerometers were installed on all 5 floors to detect lateral movements of the building structure
3 zones of major structural frame were instrumented with Full bridge strain gauges
For the 3 zones a total of 86 Full bridge strain gauges were installed on all the structural members to measure and record for the long term…
A Concrete slab area was selected and installed with sensors that were embedded in the pour, including the upper and lower surfaces of the concrete for measuring the Rebar, Bondek and concrete behaviours. A steel member central span was gauged and the Bondek, Rebar and concrete directly above also instrumented.
A networked array of 8 National Instruments DAQ units were installed around the building to gather the data from the sensors for analysis and long term data logging.
The project objective was quantifying the strains and apparent stresses at specific locations on a set of points on heavy-haul track.
The primary aim of the project was to estimate the dynamic amplification of stress (and load) on the points in the heavy haul rail environment. The scope of work included:
- Developing a test plan and gauge location map
- Hardware, software and communication equipment to facilitate project
- In-field strain gauge and accelerometer installation to the track infrastructure
- Measure strain and acceleration during several trains throughout a day of operation
- Provide immediate on-site feedback on the results after each train pass, and data files at the end of the measurement campaign
As part of Transport for NSW’s project to reduce rail squeal generated through the wheel-rail interface, EngAnalysis was involved in the measurement and analysis of rail bogie warp stiffness. This included static testing of the warp stiffness of bogies, trials to modify the warp stiffness through component changes, and on-track testing to verify changes.
EngAnalysis developed analysis and reporting software to provide the test results and statistics from the data gathered on the bogie warp testing rig and undertook a statistical review of static testing and dynamic on track test results linking angle of attack, bogie warp, warp stiffness and noise.
EngAnalysis was engaged to design, deploy, and operate a retro-fitted load monitoring system for several struts over an excavation site used to manage the risk of wall collapse. The timeframe from the beginning of concept design to deployment was less than 4 weeks.
The deployed system monitors the axial load in the 9 struts by using an array of strain gauges, with an instrumentation cabinet for logging hardware and communication. The raw data is securely uploaded to EngAnalysis data servers for processing, before being sent directly to integrate into the site’s data management system.
The system has provided significant insight into changes in loading to the struts due to the excavation as well as the effects of seasonal and daily ambient temperature and radiant heat fluctuations. To take the system further, a predictive tool which accounts for seasonal temperature variance and time dependant excavation rates was developed to forecast peak loads during summer, allowing site management to plan and make informed decisions.
This project was focused on the quantification of structural vibration in equipment racks during sea trials for the HMAS Brisbane. A world-class data acquisition system and transducers were deployed to 6 remote locations on-board the ship. A total of 90 channels of acceleration were dispersed over the ship and aggregated to the single logger.
The experiment design and analysis methodology were completed collaboratively the customer who had specific requirements for data security and military standards.
The test operated for a week-long sea trial to verify the adequacy of equipment and isolation systems during operational performance. Detailed data analysis was conducted to review the week of data against severity limit set out by military standards.
Working in collaboration with the team at CSIRO, EngAnalysis instrumented a number of structural members below the road deck and rail line on the Sydney Harbour Bridge. The instrumentation array included accelerometers and strain gauges, and the data was used to define the operational loads.
The project involved designing a weatherproof instrumentation cabinet housing equipment for power management, communications for secure data transfer, strain amplifiers and logging equipment.
A rail operator had identified a structural vulnerability in the design of a popular class of coal rollingstock with potential to result in catastrophic wagon failure during revenue service.
The detail of concern was located at a position that cannot be readily inspected without significant disassembly of the wagon structure. This was not only a costly and time consuming exercise but also provided no assurance that future failures would not occur.
EngAnalysis devised and successfully demonstrated a low-cost method of assessing the structural integrity of coal rollingstock during revenue service.
The solution required the development of custom wireless electronics capable of operating for up to nine years on batteries.
The system is deployed across a fleet of wagons to provide real-time assurance of structural health and facilitate preventative maintenance interventions before failure occurs.
A rail operator identified widespread structural cracking in a critical location of their fleet. These wagons presented recurrent cracks on welds at critical location much sooner than expected.
EngAnalysis provided testing and analysis services to review the fatigue issues and guide a repair strategy. Within 5 minutes of the operational testing, the strain gauge results disproved the original hypothesis and identified an un expected load case due to wagon dynamics.
The strain data was analysed for load reconstruction using the unit load FEA results. The load reconstruction data was able to represent the test data within 5%.
The outcome of this investigation illustrated that the primary mode of failure was not caused by the expected load. This made it possible to design simple remedial changes that targeted the root cause of the failures at the welds on the existing wagons to maximise life.
The project provided large savings in the simplicity of the repair, and highlighted the value that measurement and data analysis combined with computational modelling can provide.
EngAnalysis provided design guidance, validation and test requirements for safety systems on manual turf harvesters.
Manual stacking turf harvesters lack modern safety systems, this has resulted in at least one known fatality and numerous injuries. Automated stacking harvesters are becoming the norm, but many farmers still use manual stackers regularly in certain situations. SafeWork NSW ruled that harvesters must meet certain guidelines in order to be used safely, however this guidance lacked specificity in how to implement changes that would lead to compliance. OEM suppliers showed little interest in providing solutions.
Our team worked closely with a local grower and the turd growers bodies who had proactively developed a design they felt was appropriate.
EngAnalysis reviewed the Coroner’s reports, SafeWork NSW guidance, Australian standards and the growers design modifications. We provided design generic and detail guidance, and testing procedures, pass/fail criteria and operational guidance to ensure individual farmers could implement design modifications cost effectively and safely. Our engineers tested the original design and provided design rectification guidance where required. We also attended a ‘Growers Open Day’ to provide individual guidance where required.
