Buckling restrained braced frame

Abstract

A buckling restrained braced frame for use in light-framed constructions which includes a ductile load bearing core surrounded by a lightweight casing which resists buckling of the core under compressive loads.

1 . A buckling restrained brace for use in a buckling restrained braced frame, comprising: 
 a core; and    a casing surrounding at least a portion of the core for resisting buckling of the core under compressive loads on the core, the casing being formed of wood.    
   
   
       2 . A buckling restrained brace as recited in  claim 1 , wherein the casing is formed from two separate halves that are affixed together.  
   
   
       3 . A buckling restrained brace as recited in  claim 2 , wherein the separate halves are affixed to each other by at least one of an adhesive, an epoxy, screws, nails, bolts, and a mending plate provided at an intersection between the halves.  
   
   
       4 . A buckling restrained brace as recited in  claim 2 , wherein the separate halves are affixed to each other by at least one of a rope, a strap, and a band applied around the halves.  
   
   
       5 . A buckling restrained brace as recited in  claim 2 , wherein the separate halves are affixed to each other by a wrap applied around the outer surface of the casing once the halves are joined together.  
   
   
       6 . A buckling restrained brace as recited in  claim 2 , wherein the separate halves are affixed to each other by means for preventing slip between the halves.  
   
   
       7 . A buckling restrained brace as recited in  claim 2 , wherein each half of the casing is formed with a channel for receiving the core when the halves are affixed together, the core lying in contact with at least one surface defining at least one of the channels when the halves are affixed together.  
   
   
       8 . A buckling restrained brace as recited in  claim 1 , wherein the core is ductile.  
   
   
       9 . A buckling restrained brace as recited in  claim 1 , wherein the core has a circular diameter through a plane perpendicular to a central axis of the core.  
   
   
       10 . A buckling restrained brace as recited in  claim 1 , wherein the core has a diameter through a plane perpendicular to a central axis of the core in the shape of one of a square, a rectangle, an oval, an ellipse, or cross-shaped.  
   
   
       11 . A buckling restrained brace as recited in  claim 1 , wherein the casing has an outer surface which is in the shape of one of a square, a rectangle, a circle, an oval, and an ellipse.  
   
   
       12 . A buckling restrained brace as recited in  claim 1 , wherein the casing has an outer surface including rounded edges.  
   
   
       13 . A buckling restrained brace as recited in  claim 1 , wherein the casing includes an opening through its center, the opening being substantially square.  
   
   
       14 . A buckling restrained brace as recited in  claim 1 , wherein the casing includes an opening through its center, the opening substantially conforming in shape to the core.  
   
   
       15 . A buckling restrained brace as recited in  claim 1 , wherein the casing is formed of four separate sections which may be affixed to each other to define an opening capable of at least partially enclosing the core.  
   
   
       16 . A buckling restrained brace as recited in  claim 1 , further comprising a pair of tubular extensions affixed to first and second ends of the core, the pair of tubular extensions affixing the core to a frame of the buckling restrained braced frame.  
   
   
       17 . A buckling restrained brace as recited in  claim 16 , wherein a tubular extension of the pair of tubular extensions has a threaded bore for mating with threads on the first or second end of the core.  
   
   
       18 . A buckling restrained brace as recited in  claim 16 , wherein a tubular extension of the pair of tubular extensions is welded to the first or second end of the core.  
   
   
       19 . A buckling restrained brace for use in a buckling restrained braced frame, comprising: 
 a core; and    a casing surrounding at least a portion of the core for resisting buckling of the core under compressive loads on the core, the casing being formed of a material from a group of materials including: 
 wood,  
 metals including aluminum, copper, brass, bronze and alloys thereof,  
 polymers including rigid plastic, and  
 fiberglass.  
   
   
   
       20 . A buckling restrained brace as recited in  claim 19 , wherein the casing is formed from two separate halves that are affixed together.  
   
   
       21 . A buckling restrained brace as recited in  claim 19 , wherein the casing is formed from a unitary member with an opening capable of at least partially enclosing the core.  
   
   
       22 . A buckling restrained brace as recited in  claim 20 , wherein the separate halves are affixed to each other by means for preventing slip between the halves.  
   
   
       23 . A buckling restrained brace as recited in  claim 19 , wherein the core has a diameter through a plane perpendicular to a central axis of the core in the shape of one of a circle, a square, a rectangle, an oval, an ellipse, or cross-shaped.  
   
   
       24 . A buckling restrained brace as recited in  claim 19 , wherein the casing has an outer surface which is in the shape of one of a square, a rectangle, a circle, an oval, and an ellipse.  
   
   
       25 . A buckling restrained brace as recited in  claim 19 , wherein the casing has an outer surface including rounded edges.  
   
   
       26 . A buckling restrained brace as recited in  claim 19 , wherein the casing includes an opening through its center, the opening substantially conforming in shape to the core.  
   
   
       27 . A buckling restrained brace as recited in  claim 19 , further comprising a pair of tubular extensions affixed to first and second ends of the core, the pair of tubular extensions affixing the core to a frame of the buckling restrained braced frame.  
   
   
       28 . A buckling restrained brace for use in a buckling restrained braced frame, comprising: 
 a core; and    means for resisting buckling of the core under compressive loads on the core.    
   
   
       29 . A buckling restrained braced frame for hysteretic damping in light-framed constructions, comprising: 
 a frame; and    a buckling restrained brace, including 
 a core, and  
 a casing surrounding at least a portion of the core for resisting buckling of the core under compressive loads on the core, the casing being formed of a material from a group of materials including: 
 wood,  
 metals including aluminum, copper, brass, bronze and alloys thereof,  
 polymers including rigid plastic, and fiberglass.  
 
   
   
   
       30 . A buckling restrained brace as recited in  claim 29 , wherein the casing is formed from two separate halves that are affixed together.  
   
   
       31 . A buckling restrained brace as recited in  claim 29 , wherein the casing is formed from a unitary member with an opening capable of at least partially enclosing the core.  
   
   
       32 . A buckling restrained brace as recited in  claim 30 , wherein the separate halves are affixed to each other by means for preventing slip between the halves.  
   
   
       33 . A buckling restrained brace as recited in  claim 29 , wherein the casing has an outer surface which is in the shape of one of a square, a rectangle, a circle, an oval, and an ellipse.  
   
   
       34 . A buckling restrained brace as recited in  claim 29 , wherein the casing has an outer surface including rounded edges.  
   
   
       35 . A buckling restrained brace as recited in  claim 29 , wherein the casing includes an opening through its center, the opening substantially conforming in shape to the core.  
   
   
       36 . A buckling restrained brace as recited in  claim 29 , further comprising a pair of tubular extensions affixed to first and second ends of the core, the pair of tubular extensions affixing the core to a frame of the buckling restrained braced frame.  
   
   
       37 . A buckling restrained brace for use in a buckling restrained braced frame capable of hysteretic damping of shear forces, the buckling restrained brace comprising: 
 a core; and    a casing surrounding at least a portion of the core for resisting buckling of the core under compressive loads on the core, the casing being formed of a material from a group of materials including: 
 wood,  
 metals including aluminum, copper, brass, bronze and alloys thereof,  
 polymers including rigid plastic, and  
 fiberglass;  
   wherein tensile and compressive loads exerted on the core are not transferred to the casing without employing a slip layer between the core and the casing.    
   
   
       38 . A buckling restrained brace for use in a buckling restrained braced frame, comprising: 
 a core having a length;    a first conduit circumjacent about the core;    a second conduit circumjacent about the core, the first and second conduits having a combined length less than the length of the core to define a gap between the first and second conduits; and    a spring wrapped around the core within the gap between the first and second conduits, the spring biasing the first and second conduits away from each other.    
   
   
       39 . A buckling restrained brace as recited in  claim 38 , further comprising: 
 a third conduit circumjacent about the spring and at least end portions of the first and second conduits adjacent the gap.    
   
   
       40 . A buckling restrained brace as recited in  claim 39 , further comprising: 
 a casing surrounding the third conduit, and at least a portion of the first conduit, the second conduit and the core for resisting buckling of the core under compressive loads on the core, the casing being formed of wood.    
   
   
       41 . A buckling restrained brace as recited in  claim 38 , the first and second conduits formed of steel.  
   
   
       42 . A buckling restrained brace for use in a buckling restrained braced frame, comprising: 
 a core having a length;    a first conduit circumjacent about the core;    a second conduit circumjacent about the core, the first and second conduits having a combined length less than the length of the core to define a gap between the first and second conduits;    a spring wrapped around the core within the gap between the first and second conduits; and    a third conduit circumjacent about the spring and at least end portions of the first and second conduits adjacent the gap.    
   
   
       43 . A buckling restrained brace as recited in  claim 42 , further comprising: 
 a casing surrounding the third conduit, and at least a portion of the first conduit, the second conduit and the core for resisting buckling of the core under compressive loads on the core, the casing being formed of wood.