Wednesday, August 31, 2011

Dana Hall Repairs





Dana Hall, on the campus of SUNY College of Technology in Canton, New York, was constructed in 1969. It was built to accommodate the College’s athletic teams and physical education classes. The main framing consisted of Glulam arch frames spaced at 18’ centers spanning 108’-6”.



About two years after the building was opened, cracks were noticed at the moment splice locations which concerned the owners enough to call for a series of inspections. It was determined that the cracks were not structurally significant as long as they did not propagate but since the cracks were evident in the same location in each of the Glulam frames, this confirmed that an inherent issue existed with the design. It was decided that the splits would be “monitored” to make sure they didn’t progress further.

In 1998 Canton experienced a heavy snow storm. In 2006, maintenance personnel noticed that the cracks had propagated and opened further. Following another inspection, an attempt was made to repair the most heavily split arch frame using lag screws inserted from the bottom of the arch. But new splits occurred after the lag screws were installed near the tops of the new lags so a second attempt was made to close the splits using steel angles and an HSS section to clamp the arches.

These attempts proved unsuccessful so the College began exploring the cost to demolish the building. Initial demolition estimates were in the vicinity of $2.3 million. But before the final decision was made to demolish the building, the College decided to make one final attempt to repair the Glulam frames. An internet search led them to Western Wood Structures who was hired to perform an inspection, complete a structural analysis, and make recommendations for a permanent solution.

The College decided to accept Western Wood’s opinion that the frames could be repaired as well as brought to current code and the decision was then made to advertise the job to the general public on a design-build basis. Western Wood turned in a bid and was eventually awarded the contract for just over $1.1 million.

There were four repair and code upgrade methods used by Western Wood Structures to complete the necessary repairs:

1. The frames were post-tensioned due to being over stressed in bending;



















2. Additional laminations were added due to being over stressed in bending;






















3. Shear dowels were installed to restore the shear capacity of the members. Some of the holes drilled into the arch frames were 54" deep;






















4. Side plates were installed at the moment splice locations to transfer the reaction of the beam to the arch section.

















Dana Hall has been saved from the wrecking ball and today, SUNY College of Technology has a multi-use building that will safely serve their needs for many years to come.

Dana Hall Repair White Paper

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