As a subconsultant to WSP, Ayres Associates is providing primary inspection teams, condition assessment, and related engineering services for the I-275 Bob Graham Sunshine Skyway Bridge Asset Management Project for the Florida Department of Transportation (FDOT). Services include inspections of the signature bridge over Tampa Bay, including being prepared for 24/7 emergency assistance.
The Sunshine Skyway Bridge is a cable-stayed concrete segmental box girder with external and internal post-tensioning. The structure comprises low-level prestressed concrete AASHTO beam trestle spans, twin concrete segmental box girder high-level approach spans, and main concrete segmental box girder spans supported by post-tensioned hollow piers for a total length of 21,877 feet.
It is part of I-275 and US 19, connecting St. Petersburg and Bradenton. The four-lane bridge is approximately 4.14 miles long and approximately 90 feet wide.
All bridge inspection activities are conducted in accordance with National Bridge Inspection Standards and FDOT procedures and practices. Ayres was tasked with scheduling, coordination, and inspection, which includes a variety of specialized methods to access the many elements of this landmark structure, including rope access, Boson’s chair, swing stages, and man lifts. AASHTO Element reporting includes providing sufficient information regarding defects that include the source or cause, the extent (quantity), the element(s) affected, and the location and its accessibility.
The purpose is to provide asset maintenance and repair crews with enough information for them to understand the nature of the problem and its proper repair, to quantify materials needed, and identify equipment necessary to perform the work so they can plan more efficiently.
Ayres’ structural inspection group was needed for an emergency response in July 2016 after a tanker truck carrying 4,000 gallons of fuel caught fire in the southbound lanes of the bridge. Ayres inspectors were on the scene immediately and remained on-site for nearly eight hours, playing a critical role in decisions regarding immediate repairs and ultimately reopening the bridge to traffic.