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A comprehensive field instrumentation and monitoring programme was implemented to examine the loadings on the foundations of high voltage support towers. Previous work has focussed on tower frame and footing response to loads generated following a controlled sudden release of tensioned conductors from the tower cross-arms. These results have more recently been supplemented by examining the magnitude and duration of loads transmitted to the foundation systems through wind gusts. An L2 tension tower located in Mannington, UK has been instrumented with an anemometer located at the top of a tower and strain gauges fixed to the legs at ground level. A logging system constantly scans the instruments 150 times a second. When a wind velocity above a certain threshold is detected the logging system saves readings from all the instruments to flash memory. The use of a continuous memory system in the data logger allowed the passive scanning mode to store the data prior to the wind threshold being reached, this allowed the logger to permanently store the entire event.
Over 10,000,000 readings, including 1,500,000 in just one day, were uploaded to monitoringpoint.com to allow multiple users to access this data. The system could easily handle non-geotechnical parameters such as wind velocity and direction and store readings at millisecond-scale accuracy. Despite the size of this project monitoringpoint.com was able to present the results, including leg strains, simultaneously to screen. |
"Monitoringpoint has been used to disseminate over 10
million readings for the whole project so far, including
1.5 million readings for a single day.
Monitoringpoint has enabled the research team to
share the data very effectively." David Richards University of Southampton |
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Stonehenge is Britain's greatest prehistoric archaeological monument. It stands at the centre of over 2000 hectares
of chalk downland containing 450 ancient monuments. In 1986, it was designated by UNESCO as a World Heritage Site.
However, this internationally important landscape setting is blighted by the roads and traffic surrounding the Stones,
and the experience for millions of visitors is diminished as a result. There are safety and congestion problems on
the A303 where it passes Stonehenge and the residents of Winterbourne Stoke suffer from the trunk road running
through their village. Proposals include the construction of twin tunnels in order to remove the road from the
landscape around the monuments.
Due to the high groundwater levels along the route of the tunnel, dewatering works would be required during the construction process. In order to gain an understanding of the hydro geological conditions at the site several pumping tests were carried out. Two abstraction wells were installed as well as an array of piezometers to monitor groundwater levels. These were instrumented with pressure transducers connected to a data logger. During the tests the data was collected on a daily basis and uploaded to monitoringpoint.com to give the many parties involved easy access to the data. Data was reviewed via the Internet as the tests proceeded, allowing testing to be more effectively managed. |
"Our client was impressed with the quality and timeliness of the data. It was widely agreed that the presentation and dissemination of the data enabled much better management and control of the test" Dr Gary Holmes WJ GroundWater |
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The Deep Water project was set up to trial the new features on
monitoringpoint.com that allow users of Grant Instruments data loggers to
automatically upload their data and to show how the flexibility of
monitoringpoint.com allows it to work outside of the mainstream
geotechnical industry.
The project's objective is the continuous, unmanned and reliable monitoring and dissemination of river level, river temperature, rainfall, air pressure, air temperature and humidity. The installation of equipment and upload procedures took just three hours in February 2007 and it has been recording and uploading data every day ever since. Although the project started off as a simple river and environmental monitoring station, the system has caught a brilliant insight into Britain's devastating floods in July 2007. The whole system continued to work fully automated while the river rose over 2 metres in less than 12 hours following 80mm of rainfall in 18 hours. To see all the historical readings or latest data being recorded, simply register and select project Deep Water. |
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Although the project started off as a simple river and
environmental monitoring station, the system has caught
a brilliant insight into the devastating floods in July 2007.
The whole system continued to work fully automated
while the floods caused havoc around it
" Roger Chandler Keynetix Limited |
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Govan Tunnel, forming part of the Glasgow Subway System,
was constructed in the 1890's using cut and cover
techniques. The tunnel operated for over eighty years with
few problems, but during the early eighties it suffered major
movement leading to damage of the tunnel structure. It was
subsequently shown that the settlement was due to the
ingress of water and sand. In 1983 a permanent in-tunnel
wellpoint system was installed to lower the groundwater
level below the tunnel invert. However, operation of this
system became unreliable and expensive to maintain. In
2003 Strathclyde Passenger Transport (SPT) decided that
an alternative system was required. This initiated the design
and installation of the replacement system comprising
4 interconnecting shafts and 32 horizontal wells drilled
below the live running tunnels. Vital to the safe and
effective construction of the new system was the associated
instrumentation and monitoring system.
Four shafts approximately 15m deep were constructed alongside the tunnels, but existing structures meant that the shafts were up to 25m from the tunnel. In order for the existing in-tunnel wellpoint system to be removed, and to allow the drilling of the horizontal wells in the dry, a temporary dewatering system was installed. Due to concerns the groundwater was lowered in stages, the water levels were monitored hourly and the data presented via the Internet using monitoringpoint.com, allowing all parties involved to follow the progress. Strain gauges were also installed on the tunnel lining in order to monitor any loading as the works progressed. Again these were monitored and presented on monitoringpoint.com. The use of monitoringpoint.com allowed the data to be processed and presented almost instantaneously. This gave the client greater confidence in the construction team and the way in which the work was being carried out. |
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The use of monitoringpoint.com
allowed the data to be processed
and presented almost instantaneously.
This gave the client greater confidence in
the construction team and the way in which
the work was being carried out.
" Dr Gary Holmes WJ GroundWater |