US5440845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Precast concrete sandwich panels
Assignee: University of Nebraska System
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Filing: 1994-10-06
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Granted: 1995-08-15
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Expires: 2014-10-06
Abstract
Abstract To make precast concrete sandwich panels, a first concrete slab is formed having embedded in it one end of connectors which extend from it's surface in two directions with the path between the two containing only thermally insulative material, a layer insulative material is positioned adjacent to a central portion of said connectors to form a solid layer and a second layer of concrete is cast so as to receive the upper ends of said connectors. The connectors provide resistance to shear in at least two directions and include insulative high tensile strength members extending in more than one direction between the concrete slabs.
Inventors
- 👤 Maher K. Tadros
- 👤 David C. Salmon
- 👤 Amin Einea
- 👤 Todd D. Culp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:21
CPC Classifications
E; E04; E04C; E04C2/00; E04C2/02; E04C2/04; E04C2/044; E04C2/26; E04C2/284; E04C2/288; E04C5/00; E04C5/16; E04C5/162; E04C5/163
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
306 words
A composite precast concrete sandwich panel comprising: a first concrete slab having at least a first planer surface; a second concrete slab having at least a second planer surface substantially parallel to said first planer surface; a layer of insulation comprising at least one insulating material between said first and second concrete slabs; connecting means comprising at least a portion of said insulating material holding said first and second concrete slabs together wherein all thermal conductivity paths between the first and second concrete slabs have a thermal conductivity less than 3 BTU's per hour, per square foot in area, per inch in thickness for 1 degree Fahrenheit; said connecting means including at least a first elongated strand embedded in said first concrete slab having a first plurality of sections substantially parallel to said at least a first planar surface; at least a second elongated strand embedded in said second concrete slab having a second plurality of sections substantially parallel to said at least a second planer surface; and at least one elongated member having a longitudinal axis extending at least over a portion of its length at an angle to the normal to said first planer surface; said at least one elongated member connecting sections of said at least a first elongated strand with sections of said at least a second elongated strand wherein said at least a first elongated strand is held to said at least a second elongated strand; said connecting means providing resistance to shear in at least two directions with a shear strength between the first concrete slab and second concrete slab at least sufficient to withstand 110 percent of the weight of each square foot of one of the first and second concrete slabs, wherein the connecting means takes up at least 50 percent of the full composite action shear forces.
Claim 2
Dependent Claim
306 words
A composite precast concrete sandwich panel comprising: a first concrete slab having at least a first planer surface; a second concrete slab having at least a second planer surface substantially parallel to said first planer surface; a layer of insulation comprising at least one insulating material between said first and second concrete slabs; connecting means comprising at least a portion of said insulating material holding said first and second concrete slabs together wherein all thermal conductivity paths between the first and second concrete slabs have a thermal conductivity less than 3 BTU's per hour, per square foot in area, per inch in thickness for 1 degree Fahrenheit; said connecting means including at least a first elongated strand embedded in said first concrete slab having a first plurality of sections substantially parallel to said at least a first planar surface; at least a second elongated strand embedded in said second concrete slab having a second plurality of sections substantially parallel to said at least a second planer surface; and at least one elongated member having a longitudinal axis extending at least over a portion of its length at an angle to the normal to said first planer surface; said at least one elongated member connecting sections of said at least a first elongated strand with sections of said at least a second elongated strand wherein said at least a first elongated strand is held to said at least a second elongated strand; said connecting means providing resistance to shear in at least two directions with a shear strength between the first concrete slab and second concrete slab at least sufficient to withstand 110 percent of the weight of each square foot of one of the first and second concrete slabs, wherein the connecting means takes up at least 50 percent of the full composite action shear forces.
Claim 3
Dependent Claim
45 words
A panel in accordance with claim 1 in which the at least one elongated member is mounted at opposite ends to different ones of the concrete slabs and includes heat insulative high tensile strength members extending in more than one direction between the concrete slabs.
Claim 4
Dependent Claim
23 words
A panel in accordance with claim 2 in which the at least one elongated member includes at least one fiber reinforced plastic member.
Claim 5
Dependent Claim
279 words
A building containing at least one precast concrete sandwich panel, comprising: said precast concrete sandwich panel being mounted to carry load; said panel comprising at least a first and second concrete slab and insulative material between first and second concrete slabs; said panel being a composite structural panel in which every thermal conductivity path has a thermal conductivity less than 3 BTU's per hour, per square foot in area, per inch in thickness for 1 degree Fahrenheit between the first and second concrete slabs; said panel including at least a first elongated strand embedded in said first concrete slab having a first plurality of sections substantially parallel to said at least a first planar surface; at least a second elongated strand embedded in said second concrete slab having a second plurality of sections substantially parallel to said at least a second planar surface; and at least one elongated connecting member; said at least one elongated connecting member having a longitudinal axis and being capable of transmitting tensile forces in at least two directions between said first and second concrete slabs at an angle to the normal of surfaces of said first and second concrete slabs and being of good thermal insulated material having a thermal conductivity less than 3 BTU's per hour, per square foot in area, per inch in thickness for 1 degree Fahrenheit positioned between and connecting said first and second concrete slabs; said at least one elongated member connecting sections of said at least a first elongated strand with sections of said at least a second elongated strand wherein said at least a first elongated strand is held to said at least a second elongated strand.
Claim 6
Dependent Claim
279 words
A building containing at least one precast concrete sandwich panel, comprising: said precast concrete sandwich panel being mounted to carry load; said panel comprising at least a first and second concrete slab and insulative material between first and second concrete slabs; said panel being a composite structural panel in which every thermal conductivity path has a thermal conductivity less than 3 BTU's per hour, per square foot in area, per inch in thickness for 1 degree Fahrenheit between the first and second concrete slabs; said panel including at least a first elongated strand embedded in said first concrete slab having a first plurality of sections substantially parallel to said at least a first planar surface; at least a second elongated strand embedded in said second concrete slab having a second plurality of sections substantially parallel to said at least a second planar surface; and at least one elongated connecting member; said at least one elongated connecting member having a longitudinal axis and being capable of transmitting tensile forces in at least two directions between said first and second concrete slabs at an angle to the normal of surfaces of said first and second concrete slabs and being of good thermal insulated material having a thermal conductivity less than 3 BTU's per hour, per square foot in area, per inch in thickness for 1 degree Fahrenheit positioned between and connecting said first and second concrete slabs; said at least one elongated member connecting sections of said at least a first elongated strand with sections of said at least a second elongated strand wherein said at least a first elongated strand is held to said at least a second elongated strand.
Claim 7
Dependent Claim
16 words
A building in accordance with claim 4 in which the connecting elements are fiber reinforced plastic.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-14 | 1999-02-13 | 1999-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-14 | 2003-02-13 | 2003-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-14 | 2007-02-13 | 2007-08-15 | $7700.00 | Window Closed / Lapsed |