Reinforced structural member and method of forming

Abstract

A new and useful structure and method for reinforcing a structural member is provided. A fabric cover on a selected portion of the structural member; wherein (a) the fabric cover comprises a plurality of different carbon fiber types in a predetermined configuration, (b) each of the different carbon fiber types has a different modulus of elasticity than the other carbon fiber types, and each of the different carbon fiber types being of a type and in an orientation such that it will carry at least a part of an impact load due to pressure wave impact, inertia loading due to ground motion forces, and combinations of the foregoing, and (c) the predetermined configuration and the different modulus of elasticity of the different carbon fiber types designed to react to energy from forces due to pressure wave impacts, inertia loading due to ground motion forces, and combinations of the foregoing, in a manner such that higher modulus carbon fiber types will fracture before lower modulus carbon fiber types, so that in dissipating the energy of the impact load when the higher modulus carbon fibers break, the lower modulus carbon fiber types.

1 . A reinforced structural member comprising a structural member and a fabric cover on a selected portion of the structural member; wherein 
 a. the fabric cover comprises a plurality of different carbon fiber types in a predetermined configuration,    b. each of the different carbon fiber types has a different modulus of elasticity than the other carbon fiber types, and each of the different carbon fiber types being of a type and in an orientation such that it will carry at least a part of an impact load due to pressure wave impact, inertia loading due to ground motion forces, and combinations of the foregoing, and    c. the predetermined configuration and the different modulus of elasticity of the different carbon fiber types designed to react to energy from forces due to pressure wave impacts, inertia loading due to ground motion forces, and combinations of the foregoing, in a manner such that higher modulus carbon fiber types will fracture before lower modulus carbon fiber types, so that in dissipating the energy of the impact load when the higher modulus carbon fibers break, the lower modulus carbon fiber will remain intact to keep the reinforced structural member together.    
   
   
       2 . A reinforced structural member as defined in  claim 1 , wherein the fabric cover comprises at least two different types of carbon fibers, each of which has a different modulus of elasticity than the other carbon fiber types, and each carbon fiber type being in a pattern such that when subjected to energy from forces due to pressure wave impacts, inertia loading due to ground motion forces, and combinations of the foregoing, the carbon fiber type with the highest modulus of elasticity will fracture first, and the carbon fiber type with the next highest modulus of elasticity will fracture next, so that in dissipating the energy of the impact load when the higher modulus carbon fibers break, the lower modulus carbon fiber types should be able to carry the remaining impact loads, and the likelihood of fracture of the carbon fiber type with the lowest modulus of elasticity is minimized.  
   
   
       3 . A reinforced structural member as defined in  claim 2 , wherein the fabric cover comprises (i) first type of carbon fibers having a minimum modulus of elasticity of 90 MSI, (ii) second type of carbon fibers with a minimum modulus of elasticity of 60 MSI, and (iii) third type of carbon fibers with a minimum modulus of elasticity of 30 MSI.  
   
   
       4 . A reinforced structural member as defined in  claim 3 , wherein the first, second and third types of carbon fibers each have a raw fiber tensile strength of at least 500 KSI, and each of the first second and third types of fibers forms about ⅓ d of the fiber used to form the fabric cover.  
   
   
       5 . A reinforced structural member as defined in  claim 4 , wherein the fabric cover includes a woven fabric that includes at least the first, second and third types of carbon fibers defined in  claim 4 .  
   
   
       6 . A reinforced structural member as defined in  claim 5 , wherein the woven fabric includes (i) a first orientation of fibers in which fibers of the first, second, and third types of carbon fibers extend parallel to each other, and (ii) a second orientation of fibers in which fibers of the first, second and third types of carbon fibers extend transverse to the first orientation of fibers.  
   
   
       7 . A reinforced structural member as defined in  claim 6 , wherein the structural member has opposite sides and a fabric cover is applied to each of the opposite sides of the structural member, and wherein the cover applied to each of the opposite sides comprises a plurality of layers of woven fabric, each layer of woven fabric having the structure of  claim 6 .  
   
   
       8 . A reinforced structural member as defined in  claim 7 , wherein the fabric cover is bonded by epoxy to each of the opposite sides of the structural member.  
   
   
       9 . A reinforced structural member as defined in  claim 3 , wherein the fabric cover includes a woven fabric that includes at least the first, second and third types of carbon fibers defined in  claim 3 .  
   
   
       10 . A reinforced structural member as defined in  claim 9 , wherein the woven fabric includes (i) a first orientation of fibers in which fibers of the first, second, and third types of carbon fibers extend parallel to each other, and (ii) a second orientation of fibers in which fibers of the first, second and third types of carbon fibers extend transverse to the first orientation of fibers.  
   
   
       11 . A reinforced structural member as defined in  claim 10 , wherein the structural member has opposite sides and a fabric cover is applied to each of the opposite sides of the structural member, and wherein the cover applied to each of the opposite sides comprises a plurality of layers of woven fabric, each layer of woven fabric having the structure of  claim 10 .  
   
   
       12 . A reinforced structural member as defined in  claim 11 , wherein the fabric cover is bonded by epoxy to each of the opposite sides of the structural member.  
   
   
       13 . A method of reinforcing a structural member comprising the steps of 
 (a) providing a woven fabric cover comprising a plurality of different carbon fiber types woven into a predetermined configuration, each of the different carbon fiber types having a different modulus of elasticity than the other carbon fiber types, and each of the different carbon fiber types being of a type and in an orientation such that it will carry at least a part of an impact load due to pressure wave impact, inertia loading due to ground motion forces, and combinations of the foregoing, and the predetermined configuration and the different modulus of elasticity of the different carbon fiber types designed to react to energy from forces due to pressure wave impacts, inertia loading due to ground motion forces, and combinations of the foregoing, in a manner such that higher modulus carbon fiber types will fracture before lower modulus carbon fiber types, so that in dissipating the energy of the impact load when the higher modulus carbon fibers break, the lower modulus carbon fiber types should be able to remain intact to keep the reinforced structural member together, and    (b) applying the woven fabric to the structural member in a predetermined fashion that orients the different types of carbon fibers to cause them to react to energy from forces due to pressure wave impacts, inertia loading due to ground motion forces, and combinations of the foregoing, in a manner such that higher modulus carbon fiber types will fracture before lower modulus carbon fiber types, so that in dissipating the energy of the impact load when the higher modulus carbon fibers break, the lower modulus carbon fiber types should will remain intact to keep the reinforced structural member together.    
   
   
       14 . A method as defined in  claim 13 , wherein the fabric cover comprises at least two different types of carbon fibers, each of which has a different modulus of elasticity than the other carbon fiber types, and each carbon fiber type being in a pattern such that when subjected to energy from forces due to pressure wave impacts, inertia loading due to ground motion forces, and combinations of the foregoing, the carbon fiber type with the highest modulus of elasticity will fracture first, and the carbon fiber type with the next highest modulus of elasticity will fracture next, so that in dissipating the energy of the impact load when the higher modulus carbon fibers break, the lower modulus carbon fiber types should be able to carry the remaining impact loads, and the likelihood of fracture of the carbon fiber type with the lowest modulus of elasticity is minimized.  
   
   
       15 . A reinforced structural member as defined in  claim 14 , wherein the fabric cover comprises (i) first type of carbon fibers having a minimum modulus of elasticity of 90 MSI, (ii) second type of carbon fibers with a minimum modulus of elasticity of 60 MSI, and (iii) third type of carbon fibers with a minimum modulus of elasticity of 30 MSI.  
   
   
       16 . A method as defined in  claim 15 , including the step of bonding the fabric cover by epoxy to the structural member.