A shipyard in Virginia fabricated a caisson weighing 341,000 pounds inside its newly constructed shop. It needed to be transported to a nearby dock, but to do so, the 23' 5"-tall piece had to clear a doorway that was barely 24' in height. Barnhart’s competition proposed cutting the customer’s brand-new doorway taller to accommodate the caisson on a self-propelled modular transporter.
Barnhart’s solution involved jacking and sliding the caisson out of the building less than an inch off the ground on stands and slide shoes. The team leapfrogged slide track for the approximately 200-foot-long slide distance. The caisson was brought out of the building with just six inches to spare.
The team used pull-up gantries (PUGs) to lift the caisson onto a Goldhofer trailer. Steel mats and stands were used on the trailer to provide stability. The caisson was then hauled to the dock on the trailer, at one point crossing over a culvert that was jumped with barge ramps.
After a journey of approximately a mile, the caisson was successfully delivered to the customer’s dockside gantry. Barnhart’s solution helped the customer avoid cutting their doorway, saving them money and time. Also, utilizing PUGs and jack houses versus traditional jacks eliminated the need for crib stacks, which saved even more time.