Cold-formed steel above ground tornado shelter

Abstract

A tornado shelter which meets the structural performance criteria of ICC, FEMA, ASCE, AISI, and ACI, produced from trapezoidal cold-formed steel panels.

1 . A commercial package comprising:
 a plurality of roll-formed steel components, each component:
 having a primary axis 
 being elongated in the direction of the primary axis 
 having a substantially constant profile when viewed along any section normal to the primary axis, the profile including a trough 
   the plurality of components being adapted to be bolted to one another to form a plurality of arch assemblies, each arch assembly
 having a primary axis coincident with the primary axes of the components forming said each assembly 
 being elongated in the direction of the primary axis 
 having a substantially constant profile when viewed along any section normal to the primary axis, the profile including a trough 
   the plurality of arch assemblies being adapted to be bolted to one another in horizontally side by side relation to define an arch having a pair of walls and span connecting the walls   the arch being adapted such that, when the walls are operatively secured to the ground, the arch is capable of meeting one or more of:   ICC 500, FEMA 361, IBC, ASCE 7, AISI S100, and ACI 318 for 250 mph tornado wind forces, 100 mph 15-lb sawn lumber 2×4 missile impacts, and 100 psf roof live loads.   
     
     
         2 . A commercial package according to  claim 1 , wherein:
 the diameter of the arch is 8′ or greater;   the walls are constructed of steel between 18 and 20 gauge; and   the span is constructed of steel between 18 and 22 gauge.   
     
     
         3 . A commercial package according to  claim 1 , wherein, in respect of each component, the trough is a trapezoidal trough. 
     
     
         4 . A method of assisting a consumer with the securement of a tornado shelter, the method comprising the steps of:
 offering the commercial package of  claim 1  for sale; and   providing assistance in the installation of the commercial package.   
     
     
         5 . A method according to  claim 3 , wherein the assistance is provided in the form of one or more of instructions accompanying the commercial package in shipment and the service of installation of the commercial package. 
     
     
         6 . Use of a steel arch building as an ICC-compliant residential shelter or ICC-compliant small community shelter, the steel arch building comprising:
 an arch having a pair of walls and a span connecting the walls, the arch being defined by a plurality of arch assemblies bolted to one another in horizontally side by side relation, the walls being operatively secured to the ground,   each arch assembly being defined by a plurality of roll-formed steel components and
 having a primary axis 
 being elongated in the direction of the primary axis 
 having a substantially constant profile when viewed along any section normal to the primary axis, the profile including a trough 
   each component:
 having a primary axis coincident with the primary axis of the arch assembly of which it forms part 
 being elongated in the direction of the primary axis 
 having a substantially constant profile when viewed along any section normal to the primary axis, the profile including a trough. 
   
     
     
         7 . Use according to  claim 6 , wherein:
 the diameter of the arch is 8′ or greater;   the walls are constructed of steel between 18 and 20 gauge; and   the span is constructed of steel between 18 and 22 gauge.   
     
     
         8 . Use according to  claim 7 , wherein, in respect of each component, the trough is a trapezoidal trough. 
     
     
         9 . A commercial package according to  claim 1 , wherein the arch is capable of meeting the ICC-500 Shelter Standard.