During February 2011, heavy snowfall with a sustained period of below-freezing temperatures resulted in significant snow accumulation in the northeast United States. SGH investigated reported fractures in glue-laminated (glulam) timber roof beams at three different armory buildings that occurred within hours. After overseeing emergency shoring of the fractured beams, SGH designed permanent repairs to restore the strength of the damaged beams.
SGH determined the long-span, curved, glulam beams failed in radial tension under snow loads and needed to be shored immediately. We assisted contractors in developing an emergency shoring plan.
As the engineer of record, SGH designed and oversaw repairs to several beams. Highlights of our work include the following:
Developed a repair program to maintain overhead clearance in the buildings and allow them to remain occupied
Designed a repair sequence, including jacking and shoring the beams at mid-span to alleviate dead load stresses, clamping the fractured beam sections together using steel saddle assemblies, and installing large-diameter, full-thread lag screws from above to restore the fractured sections
Coordinated repairs operations with occupants present during construction
Provided construction administration services, including reviewing contractor submittals, observing construction progress, and reviewing contractor applications for payment
