At more than 1,000 feet long, 250 feet wide, and 170 feet tall each, two blimp hangars constructed in the 1940s at Moffett Field are among the world’s largest clear-span timber structures. One of these hangars had significant damage to many of its timber truss arches, and the damage was progressing along the length of the hangar to the extent that there was concern the hangar, or portions of it, could collapse. Power retained Liftech to design systems to stabilize and provide access so Power could safely perform repairs. Some of these systems include:
An adjustable pipe shoring system extending from the hangar concrete floor to multiple points on the lower chord of the truss arches to support the deformed trusses.
An access shoring tower that was pulled through the hangar on channel tracks and steel rollers, so workers could shore the arches and access them for repairs.
Strand jack towers for assembling the access shoring tower inside the hangar.
A jacking procedure and system for lifting and repairing a 20-foot x 22-foot x 200-foot timber box beam over the 120-foot-tall hangar doors.
A variety of timber emergency repair details.
Reference:
Power Engineering Construction Company
Alameda, California, USA