In December 2013, Bertha ceased operation 35m underneath Seattle after complications with the front end were discovered. Mammoet was contracted to lift the 2,000t cutter head from a man-made, 35m deep shaft for repair and lower it back down once repairs were complete. The company successfully completed the task by designing and fabricating a unique custom-engineered gantry tower with one of the world’s first hydraulic equalization system, which evenly dispersed the forces exerted by lifting and tilting the load.
This system was necessary, as the gantry tower would stand on existing concrete piles used for tunnel stabilization, which were not designed to support loads at height. The result was a self-balancing tower gantry that ensured the stability of the entire lifting operation. The award ceremony took place on 30 April, during the Specialized Carriers and Rigging Association’s Annual Conference 2016 in Orlando, Florida, USA.
The Job of the Year Competition recognises SC&RA members that solve problems encountered in rigging with innovative ideas, solutions and techniques while maintaining the highest of safety standards.
