CNS Working to Repair Cracked Concrete Beams

Structural engineers at Y-12 are starting preliminary design work to stabilize a concrete beam in Building 9204-2 where vertical and horizontal cracks were found, according to a letter sent from the Oak Ridge Energy Department site office to the Defense Nuclear Facilities Safety Board released yesterday. The beam is 36 inches deep and 16 inches wide, and had a vertical crack mid-span “appearing to be almost the full depth of the beam and roughly 3/8 in. wide,” the letter states. Y-12 contractor Consolidated Nuclear Security became aware of the issue in June after a structural engineer inspected the area after receiving reports of chips of spalled concrete falling from the ceiling. The engineer also found horizontal cracks about five feet in length near the level of the lower reinforcing bar.

 

Another same-sized beam had horizontal cracks and a thinner vertical crack “The ceiling area has staining on the concrete indicative of solution leaks from legacy processing that was conducted on the floor above years ago,” the letter states. “The CNS structural engineer informed the shift manager of the cracks, who directed the area to be cordoned off to prevent unauthorized entry.” According to the July 10-dated letter, the area below the beam with the wider vertical crack is “heavily congested,” so a design solution will involve more than installing a simple vertical column and might include constructing a structural steel support frame. CNS did not respond to a Weapons Complex Morning Briefing request for comment. Aging infrastructure has been a worsening issue throughout the weapons complex, and DOE is implementing plans to modernize several of its weapons facilities.