# US 6,048,594 A · Filled composite structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,048,594 A - Document ID: US6048594A - Status: Granted - Kind: A - Application number: 09/325,631 - Filed: 1999-06-04 - Granted: 2000-04-11 - Earliest claimed: 1992-07-20 - Assignees: Lancaster Composite - Inventors: Robert H. Greene - Web page: https://patentgrep.com/patent/US6048594A ## CPC - E04C 5/07: Reinforcing elements of material other than metal, e.g. of glass, of plastics, or not exclusively made of metal (metal elements with non-structural coatings E04C5/01) - E04C 3/34: of concrete other stone-like material, with or without permanent form elements, with or without internal or external reinforcement, e.g. metal coverings (E04C3/36 takes precedence) - E04H 12/02: Structures made of specified materials - E04H 12/12: of concrete or other stone-like material, with or without internal or external reinforcements, e.g. with metal coverings, with permanent form elements - E04H 17/20: Posts therefor - Y10T 428/1314: Contains fabric, fiber particle, or filament made of glass, ceramic, or sintered, fused, fired, or calcined metal oxide, or metal carbide or other inorganic compound [e.g., fiber glass, mineral fiber, sand, etc.] - Y10T 428/1372: Randomly noninterengaged or randomly contacting fibers, filaments, particles, or flakes - Y10T 428/1393: Multilayer [continuous layer] - E04C: STRUCTURAL ELEMENTS; BUILDING MATERIALS (for bridges E01D; specially designed for insulation or other protection E04B; elements used as building aids E04G; for mining E21; for tunnels E21D; structural elements with broader range of application than for building engineering F16, particularly F16S) - E04H: BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL (foundations E02D) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A filled structure includes a fiber reinforced resinous hollow structure having a tensile strength of at least 30,000 psi, an inside surface forming a boundary which encloses a space, and a hard core within the space. The hard core has a density of at least 35 pounds per cubic foot and a compressive strength of at least 1500 psi. The hard core is formed from a mixture of particulate cementitious material and liquid such that when the mixture hardens, the hard core is mechanically locked to the inside surface of the hollow structure. ## Claims ### Claim 1 A filled structure characterized by the combination of high compressive strength and tensile strength to allow a high bending load, the filled structure comprising: a fiber reinforced resinous hollow structure having a tensile strength of at least 30,000 psi, and an inside surface forming a boundary which defines a space, and a hard core within said space, the hard core having a density of at least 35 pounds per cubic foot and a compressive strength of at least 1500 psi, the hard core being formed from a mixture of particulate cementitious material and liquid such that when said mixture hardens, said hard core is joined securely to said inside surface of said hollow structure. ### Claim 2 (depends on 1) The filled structure of claim 1, wherein said mixture is such that it expands its volume as it hardens, expansion of the mixture being restrained by the hollow structure and the hard core exerts a force against the inside surface of the hollow structure. ### Claim 3 (depends on 1) The filled structure of claim 1, wherein the hollow structure is a closed section. ### Claim 4 (depends on 1) The filled structure of claim 1, wherein the hollow structure is a cylindrical pipe having fiberglass rovings therein. ### Claim 5 (depends on 1) The filled structure of claim 1, wherein the mixture from which the core is formed includes a Portland cement. ### Claim 6 (depends on 5) The filled structure of claim 5, wherein the mixture from which the core is formed includes stone, sand, water, Portland cement and an additive which causes expansion of the mixture as it hardens. ### Claim 7 (depends on 1) The filled structure of claim 1, further including a coating attached on the outside of the hollow structure with the coating comprising a material which absorbs or shields ultraviolet radiation. ### Claim 8 (depends on 1) The filled structure of claim 1, wherein said hard core includes material therein selected from the group consisting of silica fume, metal, glass and polymer fibers. ### Claim 9 (depends on 1) The filled structure of claim 1, wherein said hollow structure has fiber rovings throughout an entire thickness thereof. ### Claim 10 (depends on 1) The filled structure of claim 1, wherein said hard core is of material such that shrinkage thereof is negligible upon hardening. ### Claim 11 A filled structure characterized by the combination of high compressive strength and tensile strength to allow a high bending load, the filled structure comprising: a fiber reinforced resinous hollow structure having a tensile strength of at least 30,000 psi, and an inside surface forming a boundary which defines a space, and a hard core within said space and engaged with said inside surface, the hard core having a density of at least 35 pounds per cubic foot and a compressive strength of at least 1500 psi, the hard core being formed from a mixture of particulate cementitious material and liquid. ### Claim 12 (depends on 11) The filled structure according to claim 11, wherein said mixture is such that it expands its volume as it hardens, expansion of the mixture being restrained by the hollow structure and the hard core exerts a force against the inside surface of the hollow structure.