Structural Monitoring of the UNI-Dome
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The UNI-Dome is a multi-purpose coliseum. The indoor facility is a 424-ft-diameter domed structure seating approximately 16,500 for sporting events and 25,500 for concerts. The original UNI-Dome was a cable-restrained low-profile air-supported roof with compression ring built in 1976 at a cost of $7.5 million. Three times in its history the dome encountered difficulties that caused the roof fabric to sag, accumulate water and subsequently tear.
In 1998, a hybrid roof system was installed to replace the air-supported roof. Stainless steel, standing seam roof panels supported by structural metal deck and bar joists form the skin of the peripheral area of the roof (75% of the roof area). The center 45,000-sq-ft polygon is enclosed with an arch-supported, PTFE fabric tensile roof. The new roof system, further modified since the 1998 reconstruction, utilizes a snow-melting system to prevent snow from accumulating enough to damage the roof structure. As a backup measure, CTLGroup installed a structural monitoring system as part of the roof system retrofit.
The structural monitoring system includes wind speed and direction sensors and strain gages placed on key structural elements near the top of the roof. The strain gages are connected to a data logger that issues an alarm if assigned response values are exceeded for any sensor. The system is accessed remotely for software modification or data retrieval. This system provides continuous, real-time evaluation of the roof structure's response to high winds, snow-melt or uneven snow accumulation.