CTDOT Strain Gauge Installation & Monitoring at the Gold Star Memorial Bridge

New London, CT

AI Engineers, Inc. (AI) was tasked by CTDOT for the installation and monitoring of wireless strain gauges at 18 locations on the Northbound Gold Star Memorial Bridge (Bridge No. 03819) for the purpose of analyzing strain at selected points. A Resensys remote monitoring system was chosen, including 20 high rate strain SenSpot sensors, 2 tilt SenSpot sensors, 3 SeniMax data loggers, remote communication gateways, and 2 auxiliary signal repeaters.

AI and Resensys were asked to add 8 additional high rate strain SenSpot sensors on 8 new locations of the bridge in August 2016 for the purpose of analyzing strain and load rating on selected spans. For load testing, a truck with known weight moved through the bridge in different lanes and directions. 

AI monitors the system that has been working continuously since installation to alert all relevant parties to any change in the strain on girders, bearings, gusset plates, and truss members of the bridge. Monthly reports are prepared for the DOT that contain all collected data and recommendations based on the findings.

Bridge No. 03819 carries Interstate 95 NB over the Thames River, local roads, and railroad in New London, CT. The 27-span bridge consists of 16 girder/floorbeam/stringer spans and 11 main deck truss spans composite with a reinforced concrete deck, supported by abutments and piers. The structure was built in 1943 and rehabilitated in 1975 and 2001.

Highlights 

  • Client: CTDOT
  • Duration: 2015-2016
  • Project Scope:
    • Wireless structural monitoring
    • Remote monitoring of girders, bearings, gusset plates, & trusses 
    • Strain analysis