Dennis 2011 Piedmont tornado housing addition Just north of Falcon lake. All but 4 homes destroyed
We had a large inground shelter outside with a flat steel door. You could hold 15 people easy sitting on the benches. It was all steel set in 8+ yards of concrete. The door had 3 cross bolts to keep it closed. When the tornado hit the tubine was sucked off & the door was vibrating so much that the bolts were vibrating out of the closed position, I went up the stairs & slid them back, they started to work out again. Not much tention to hold them. I installed a bungie cord to hold them in. This may have happened with some doors the vibration may have had the handles locks etc work loose
We had a large inground shelter outside with a flat steel door. You could hold 15 people easy sitting on the benches. It was all steel set in 8+ yards of concrete. The door had 3 cross bolts to keep it closed. When the tornado hit the tubine was sucked off & the door was vibrating so much that the bolts were vibrating out of the closed position, I went up the stairs & slid them back, they started to work out again. Not much tention to hold them. I installed a bungie cord to hold them in. This may have happened with some doors the vibration may have had the handles locks etc work loose