Mobile Lidar Scan for Alcatraz Dock Pile Assessment
Moffat & Nichols was hired to do a seismic retrofit of the main dock at Alcatraz Island. They contracted with Woolpert to perform a mobile LIDAR scan of the piles supporting the pier and the seawall. In addition to georeferencing the data on the seawall and pile locations, Woolpert analyzed the data and categorized whether each pile was plumb or tilted. To accomplish these tasks, Woolpert mounted a Riegl VZ400 terrestrial laser scanner to our survey vessel Ekko and went to Alcatraz Island at 5 a.m. to catch a minus one-foot tide so the Woolpert team could capture as much of the exposed seawall and piles as possible.
