High strength light-weight fiber ash composite material, method of manufacture thereof, and prefabricated structural building members using the same

Abstract

A prefabricated structural building panel is disclosed. The panel includes a first sheet having inner and outer planar surfaces. A plurality of structural ribs are disposed on the inner surface of the first sheet and are interconnected to form a geometric design having a plurality of chambers. The first sheet and the structural ribs are integrally formed as a single unit from a fiber and fly ash composite material. In preferred form, the cement composite includes a mixture of a commercial grade fly ash having a high lime content and a dry flue-gas desulfurized fly ash.

We claim:  
     
         1 . A prefabricated structural panel for use in buildings comprising: 
 a first sheet having inner and outer planar surfaces; and    a plurality of structural ribs disposed on the inner surface of said first sheet and arranged to form a geometric design having a plurality of chambers, said first sheet and said structural ribs being integrally formed as a single unit from a fiber and fly ash composite material.    
     
     
         2 . The panel as claimed in  claim 1 , wherein said panel further comprises a second sheet formed from said fiber and fly ash composite material and having inner and outer planar surfaces, said second sheet inner surface being integrally secured to said structural ribs to close said chambers.  
     
     
         3 . The panel as claimed in  claim 2 , wherein said ribs are interconnected and said geometric design is a honeycomb.  
     
     
         4 . The panel as claimed in  claim 2 , wherein said ribs are interconnected and said geometric design is a plurality of rectangular boxes.  
     
     
         5 . The panel as claimed in  claim 1 , wherein said geometric design is a plurality of substantially parallel channels, the distal ends of each said channel being open.  
     
     
         6 . The panel as claimed in  claim 1 , wherein said chambers are filled with insulation material.  
     
     
         7 . The panel as claimed in  claim 1 , wherein said panel further comprises a second sheet formed from said fiber and fly ash composite material and having inner and outer planar surfaces, said second sheet inner surface including a second plurality of structural ribs disposed thereon arranged to form a geometric design having a plurality of open chambers facing opposite the chambers of said first sheet structural ribs, said second sheet and said structural ribs being integrally formed as a single unit from a fiber fly ash composite material with said first sheet.  
     
     
         8 . The panel as claimed in  claim 7 , wherein said panel further comprises an insulation layer interposed between said first and second sheets and filling the chambers of said geometric structural ribs of each said first and second sheets to form an integral prefabricated panel.  
     
     
         9 . The panel as claimed in  claim 7 , wherein said panel further comprises a third sheet enclosing the structural rib chambers of said first sheet, and a fourth sheet enclosing the structural rib chambers of said second sheet, and wherein said panel further comprises an insulation layer interposed between said third and fourth sheets and filling the space therebetween, said first, second, third and fourth sheets being a single integrally formed extruded panel unit.  
     
     
         10 . The panel as claimed in  claim 9 , wherein said insulation is aerated fiber fly ash.  
     
     
         11 . The panel as claimed in  claim 1 , wherein said fiber and fly ash composite material is a lightweight, quick-setting cementious material comprising fly-ash cement and organic or inorganic fibers.  
     
     
         12 . The panel as claimed in  claim 11 , wherein said composite material comprises 24-99% fly-ash cement, 0-20% fine aggregate and 1-12% fiber.  
     
     
         13 . The panel as claimed in  claim 11 , wherein the fiber of said composite material is selected from the group consisting of cellulosic fiber, PVA and polypropylene fiber.  
     
     
         14 . The panel as claimed in  claim 1 , wherein said composite material comprises a blend of fly ash cement and flue-gas desulfurized fly ash.  
     
     
         15 . The panel as claimed in  claim 14 , wherein said composite material further comprises said fly ash blend admixed with fibrous material.  
     
     
         16 . The panel as claimed in  claim 15 , wherein said fibrous material comprises organic fibers.  
     
     
         17 . The panel as claimed in  claim 14 , wherein said blend comprises 30-50% by weight of said flue-gas desulfurized fly ash.  
     
     
         18 . A prefabricated building unit designed to form a wall, floor, ceiling or roof of a building, said building unit comprising: 
 a first panel element including a first sheet having inner and outer planar surfaces and a first plurality of structural ribs disposed on the inner surface thereof with said ribs being aligned to form a geometric design having a plurality of open chambers, said first sheet and said first structural ribs being integrally formed as a single unit from a fiber fly ash composite material;    a second panel element including a second sheet having inner and outer planar surfaces and a second plurality of structural ribs disposed on the inner surface of said second sheet with said second ribs being aligned to form a geometric design having a plurality of open chambers, said second sheet and said second structural ribs being integrally formed as a single unit from a fiber fly ash composite material; and    an insulation layer interposed between said first and second panels and filling the chambers of said first and second geometric structural ribs to form an integral prefabricated building unit.    
     
     
         19 . The building unit as claimed in  claim 18 , wherein said first panel element further comprises a third sheet enclosing said first structural rib chambers of said first sheet, and wherein said second panel element further comprises a fourth sheet enclosing the chambers of said second structural ribs, said insulation layer being interposed between said third and fourth sheets and filling the space therebetween, said first, second, third and fourth sheets being a single integrally formed extruded panel unit  
     
     
         20 . The building unit as claimed in  claim 19 , wherein said the geometric design of said first plurality of structural ribs is different from the geometric design of said second plurality of structural ribs.  
     
     
         21 . The building unit as claimed in  claim 19 , wherein the chambers of said first plurality of structural ribs remain open while the chambers of said second plurality of structural ribs are filled with said insulation.  
     
     
         22 . The building unit as claimed in  claim 18 , wherein said unit includes web means disposed along opposed side edges thereof for interconnecting adjacently positioned building units.  
     
     
         23 . The building unit as claimed in  claim 18 , wherein said composite material comprises a blend of fly ash cement and flue-gas desulfurized fly ash.  
     
     
         24 . The building unit as claimed in  claim 23 , wherein said composite material further comprises said fly ash blend admixed with fibrous material of either organic or inorganic origin.  
     
     
         25 . A prefabricated wall with inner and outer panels separated by insulation, each said panel comprising a sheet having inner and outer planar surfaces and a plurality of structural ribs disposed on the inner surface thereof with said ribs being arranged to form a geometric design having a plurality of open chambers, said sheet and said structural ribs being integrally formed as a single extruded unit from a fiber fly ash composite material.  
     
     
         26 . The prefabricated wall as claimed in  claim 25 , wherein each said panel further comprises a second sheet formed from said fiber and fly ash composite material and having inner and outer planar surfaces, said second sheet inner surface being integrally secured to said structural ribs to close said chambers.  
     
     
         27 . The prefabricated wall as claimed in  claim 26 , wherein said plurality of chambers disposed in said inner panel are filled with insulation.  
     
     
         28 . The prefabricated wall as claimed in  claim 27 , wherein said insulation comprises aerated fiber fly ash.  
     
     
         29 . A process for forming a prefabricated structural panel comprising the steps of: 
 forming a composite material comprising a fiber and fly ash composite;    forming an extrusion die, sized and shaped to extrude a panel structure of desired shape and geometry;    extruding said composite material through said die where there are a plurality of holes in the mold that allow insulation bonding material to be coextruded and simultaneously deposited into the panel structure as it is extruded;    extruding said composite material and insulation bonding material through said die onto a first conveyor belt; and    compressing said extruded composite with a second conveyor belt traveling substantially parallel with said first conveyor belt to restrain overexpansion of insulation bonding material until said composite structure has set.    
     
     
         30 . The process as claimed in  claim 29 , wherein said extruded composite panel is unitary and integral.  
     
     
         31 . The process as claimed in  claim 29 , wherein said fiber and fly ash composite is formed by admixing fly ash cement with flue-gas desulfurized fly ash to form a blended fly ash cement, and then further admixing fibrous material therewith.  
     
     
         32 . A process for forming a prefabricated structural panel comprising the steps of 
 forming a composite material comprising a fiber and fly ash composite;    extruding or depositing said composite material onto the upper surface of a first conveyor belt onto which insulating volumes have been placed in a geometric pattern;    compressing said extruded or deposited composite material while on said first conveyor belt by pressing said extruded or deposited composite material with a second conveyor belt operating substantially parallel with and over the top of said first conveyor belt; and    removing said compressed composite material from said first conveyor belt onto a third conveyor belt to enable said compressed composite material to set and harden.    
     
     
         33 . The process as claimed in  claim 32 , wherein the geometric pattern in the surface of said extruded composite material is formed by placing said geometric pattern onto the surface of said second conveyor belt so as to imprint the surface of said extruded composite material as the second conveyor belt is pressed into said material.  
     
     
         34 . The process as claimed in  claim 32 , wherein the geometric pattern in the surface of said extruded composite material is formed by placing a pattern of spheroids onto the surface of said first conveyor belt prior to extruding said composite material onto said first belt so that the composite material is applied over said spheroids and fills the voids therebetween to form the predetermined geometric pattern.  
     
     
         35 . The process as claimed in  claim 32 , wherein said fiber and fly ash composite is formed by admixing fly ash cement with flue-gas desulfurized fly ash to form a blended fly ash cement, and then further admixing fibrous material therewith.  
     
     
         36 . An extrusion process of forming a prefabricated structural panel comprising the steps of: 
 forming a composite material comprising a fiber and fly ash composite;    forming an extrusion die, sized and shaped to extrude a panel structure of desired shape and geometry;    extruding said composite material through said die alone or in combination with insulation material to be used in conjunction with said composite material;    heating said die as said composite material is extruded therethrough to accelerate the setting of said composite once extruded; and    removing said extruded composite away from said die with a conveyor mechanism to permit said extruded panel structure to set and harden.    
     
     
         37 . A low cost, lightweight cement composite having a high modulus of elasticity and a low density, said composite cement comprising a mixture of a commercial grade fly ash having a high lime content and a dry flue-gas desulfurized fly ash.  
     
     
         38 . A cement composite as claimed in  claim 37 , wherein said commercial grade fly ash comprises a lime content of greater than approximately 20 wt. %.  
     
     
         39 . A cement composite as claimed in  claim 38 , wherein said flue-gas desulfurized fly ash comprises approximately 30-50 wt. % of said fly ash mixture.  
     
     
         40 . A cement composite as claimed in  claim 37 , wherein said cement composite further comprises fibrous material.  
     
     
         41 . A cement composite as claimed in  claim 40 , wherein said composite comprises 24-99% fly-ash mixture, 0-20% fine aggregate and 1-12% fiber.  
     
     
         42 . A cement composite as claimed in  claim 41 , wherein said flue-gas desulfurized fly ash comprises approximately 30-50 wt. % of said fly ash mixture.  
     
     
         43 . A low cost light-weight cement composite having a high modulus of elasticity and a low density, said composite cement comprising a mixture of a commercial grade fly ash having a high lime content and a dry flue-gas desulfurized fly ash, and an organic or inorganic fibrous material.  
     
     
         44 . A cement composite as claimed in  claim 43 , wherein said composite comprises 24-99% fly-ash mixture, 0-20% fine aggregate and 1-12% fiber.  
     
     
         45 . A cement composite as claimed in  claim 44 , wherein said flue-gas desulfurized fly ash comprises approximately 30-50 wt. % of said fly ash mixture.