Crews in Boston are removing in sections a monolithic, 43,000-sq-ft, 4-in.-thick reinforced-concrete ceiling off an Interstate 90 tunnel using specialized trucks equipped with shipping containers and hydraulic lifts.
In the predawn hours of April 6, three flatbed trailer trucks, side by side, crept out of the Prudential Tunnel in three of the four eastbound lanes carrying a 33-ft-wide, 45-ft-long slab weighing 75,000 lb—the largest of 106 sections to be removed to date, says Cory Brett, project manager for Simpson Gumpertz & Heger (SGH), the prime design contractor.