Read on Twitter
1/4 The panoramas illustrate the importance of garage doors in structural failures. The homes on the east side of the street all have garage doors that faced the oncoming tornado. With a fast moving tornado, the strongest winds can be on the back side of the tornado where https://twitter.com/auburn_windengr/status/1355021189371097088
2/4 the translational and radial velocity vectors align. Homes facing the oncoming tornado then experience strong positive pressures on the "front" wall, which collapsed several garage doors inward, pressurizing the interior like a balloon and helping lift the roof structure off.
3/4 Roofs were attached to walls using toe-nails, which do not provide much uplift resistance, and the result is large portions of the roof structure peeling away, with some walls subsequently collapsing. We saw similar trends in the Nashville tornado.
4/4 In contrast, we also saw garage doors fail often in Hurricane Laura (2020) but the use of hurricane clips, structural wood sheathing, and anchor bolts in newer homes typically prevented the propagation of damage to the roof or other elements. #engineering
