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various structural elements. Many of the sensors are located deep inside the piers’ pile supports, requiring the cable to be threaded through the 8-foot thick pile caps, and then into a special concrete encased room where the data loggers were installed. The site was accessible by boat only, as the piers are located near the center of Lake Ponchartrain, many miles from shore.
On the day of the lateral load test, a flat panel monitor was set up on one of the piers. Geocomp’s Martin Hawkes joined Da and Francisco for the test.
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Each man took up a station on different piers separated by open water. Da manned the flat panel screen while several LADOTD engineers watched live data stream in from iSiteCentral. As back up, Francisco observed the jacks, and manually recorded the pressure. Martin manned the pier with the data loggers. The load was slowly increased to 2 million pounds, while Da showed the deflections of the pier at each stage. The maximum deflection was about 3/4 of an inch. The load test went without a hitch.
Coincidentally, the test took place soon after the famous New Orleans Mardi Gras Festival, and its successful conclusion
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capped off a memorable experience for
the Geocomp team. 
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The world’s busiest airport, Atlanta’s Hartsfield- Jackson International, is adding the new $1.2 billion Maynard H. Jackson International Terminal. As part of the expansion, the Automated People Mover (APM) trains will be extended from beneath the existing International Concourse E to the new terminal.
Geocomp and subcontractor Metals & Materials Engineers (MME) is providing performance monitoring to the project team of Berkel & Company and the Holder Manhattan Moody Hunt (HMMH) management team. The project involves the open-cut excavation of twin tunnels as wide as 67 feet in fill soils of varying composition. The tunnels are in the area of active baggage handling in Concourse
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E and in the area of Taxiway D by the control tower. The tunnels also pass through existing structural walls at Concourse E, requiring significant demolition of portions of these walls.
The excavation is braced by a soldier pile and lagging system and underpinning of the existing pile caps with hand-excavated piers to depths of about 40 feet. The movement of the adjacent existing tunnel was a concern due to the unbalanced earth load of the excavation.
Excavation in variable consistency ground can produce unexpected behavior, such as sudden deformation or ground collapse. Such an event could cause significant disruption in airport operations in the area of work, potential hazard to people, damage to equipment, and delays while safety officials, airport authorities and others decide how to proceed.
The potential for major consequences coupled with a somewhat probable chance of the occurrence of significant deformations and/or unexpected performance present considerable risk to the project.
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The HMMH/Berkel team chose a proactive and cost-effective approach to managing this risk using Geocomp’s iSiteCentral real-time monitoring program. The system provides early warnings of unacceptable or surprise performance in time so that protective measures can be implemented to stop the undesirable performance or reduce the consequences.
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