FDOT District 7: Sunshine Skyway Bridge

Structure Monitoring & Movement Studies, Pinellas County, Florida

Cumbey & Fair established geodetic control (horizontal and vertical) to serve as the basis for the initial studies to establish the “footprint” of the Sunshine Skyway Bridge for various temperature conditions that will be used in the periodic monitoring and emergency evaluation after an “Event” (storm, impact, etc) to determine if the bridge has sustained structural damage or settlement.

Horizontal and Vertical Control: Utilized eight (8) GPS units to establish horizontal and vertical control on eight (8) project control points by occupying numerous HARN and 1st Order monuments around the Bay. Longer vectors required 3 to 4 hour sessions. All points (HARN, 1st Order and our new) were occupied a minimum of two (2) times, with most at least 3 times.

Movement and Monitoring Studies:Using Real Time Kinematic (RTK) G.P.S., and a combination of conventional methods (Total Station and Conventional Levels) Cumbey & Fair has performed 5 surveys, each with planned varying extremes of temperatures, of the main span, (including the approach high level spans), to establish a “Bench Mark” to which subsequent surveys either on a planned interval basis or after an “event” (Category 5 Hurricane, object strike, truck tanker fire, etc) to verify that the bridge has not had any movement.