CONCRETE CORNER STRUCTURE WITH DIAGONALLY ORIENTED FIBER RESIN POLYMER REBAR

Abstract

A concrete corner structure with diagonally oriented fiber resin polymer rebar and method that utilizes straight rebar to reinforce the corner structure. The straight rebar i intersects with the horizontally disposed rebar in the first and second walls that form the corner structure. The straight rebar is placed at a 45-degree angle with respect to the two walls and tied to the horizontally disposed rebar. This allows for the use of straight rebar to reinforce the corner structure as opposed to a curved rebar.

Claims

1. A method for pouring concrete walls using straight rebar reinforcements comprising: placing an outside corner concrete form along a foundation to form a first and second wall that form a rectangular intersection; placing a plurality of vertical reinforcement poles in the foundation a distance away from the outside corner concrete form; attaching a plurality of straight, horizontally disposed, rebar to the vertical reinforcement poles; attaching a fiber resin polymer (FRP) rebar that: intersects with the horizontally disposed rebar in the first and second walls at a 45-degree angle to each, has a length such that a first end of the FRP rebar extends outside the rectangular intersection and into the first wall, and a second end of the FRP rebar extends outside the rectangular intersection and into the second wall; connecting the FRP rebar to the horizontally disposed rebar at each point in which they intersect; placing a concrete cover at a distance away from the horizontally disposed rebar opposite the concrete form; pouring concrete between the concrete form and concrete cover to form the first and second walls.

2. A method for pooling concrete walls using straight rebar reinforcements comprising: placing an outside corner concrete form along foundation to form first and second wall that form a rectangular intersection; placing a plurality of vertical reinforcement poles in the foundation a distance away from the outside corner concrete form; attaching a plurality of straight, horizontally disposed, rebar to the vertical reinforcement poles; attaching a straight rebar that: intersects with the horizontally disposed rebar in the first and second walls at a 45-degree angle to each, has a length such that a first end of the straight rebar extends outside the rectangular intersection and into the first wall, and a second end of the straight rebar extends outside the rectangular intersection and into the second wall; connecting the straight rebar to the horizontally disposed rebar at each point in which they intersect; placing a concrete cover at a distance away from the horizontally disposed rebar opposite the concrete form; pouring concrete between the concrete form and concrete cover to form the first and second walls.

3. The method for pouring concrete walls of claim 2 wherein straight rebar is comprised of fiber resin polymer (FRP).

4. First and second concrete poured walls forming a rectangular intersection, each wall having straight horizontally disposed rebar therein that extends from a backfill end of the intersection, through the intersection, and along the wall, and wherein the rebar in each respective first and second rail intersect each other, the improvement comprising, a fiber resin polymer (FRP) rebar that: intersects with the rebar in the first and second walls within the rectangular intersection at a 45-degree angle to each, has a length such that a first end of the FRP rebar extends outside the rectangular intersection and into the first wall, and a second end of the FRP rebar extends outside the rectangular intersection and into the second wall.

5. First and second concrete poured walls forming a rectangular intersection, each wall having straight horizontally disposed rebar therein that extends from a backfill end of the intersection, through the intersection, and along the wall, and wherein the rebar in each respective first and second wall intersect each other, the improvement comprising, a rebar that: intersects with the rebar in the first and second walls within the rectangular intersection at a 45-degree angle to each, has a length such that a first end of the rebar extends outside the rectangular intersection and into the first wall, and a second end of the rebar extends outside the rectangular intersection and into the second wall.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 shows an application of the invention for a wall.

[0013] FIG. 2 shows how a diagonal fiber reinforced polymer (FRP) rebar may instead be positioned so that it the intersects with the two primary rebars at tile location where those primary rebars intersect.

DETAILED DESCRIPTION

[0014] Unlike steel rebar, FRP rebar does not corrode, and avoids other limitations of steel rebar. These limitations include: weight, corrosiveness, high stiffness, limited fatigue resistance (cyclic loading), high thermal and electrical condutivity and high maintenance for black-steel, galvanized, and epoxy-coated rebar.

[0015] Glass fiber reinforced polymer (GFRP) rebar, such as MST-BAR® & MFX-BAR® GFRP rebar is available from B&B FRP Manufacturing Inc., 20 Haulm Road, Woodbridge, Ontario, Canada L4L, 3P6. FRP rebar is especially suitable for applications where steel rebar is limited to its properties, such as in humid, coastal, and cold areas. FRP rebar eliminates corrosion problem and costs associated with corrosion and maintenance. FRP rebar has higher strength, and better adheres to concrete than steel rebar. FRP rebar may reduce the cost of a project up to 5% as the structure does not require major maintenance for 100 years.

[0016] FIG. 1 is an overhead view of an application of the invention for a wall, such as for a residential basement wall corner. If each wall is 10″ wide they form an intersection that is a 10″ square. Each wall has a primary 101 and secondary (but optional) horizontal rebar 102 that are parallel to the sides of the wall. The primary rebar 101 is about 1.5 inches from the interior sides of the wall 103, and extends far outside of the wall intersection. The secondary rebar 102 is 20″ in length, and about 1.5 inches from the exterior (backfill) side of the wall 104, and extends about 10 inches outside of the wall intersection. The diagonal FRP rebar 105 is at a 45-degree angle and laid so it is adjacent to or crosses the primary 101 and secondary rebus 102 of each all. The FRP diagonal rebar 105 is about 17 inches in length and positioned 9.5 inches from the exterior corner of the intersection 106.

[0017] FIG. 1 may also show an application of the invention for an 8″ thick wall. The only difference between this 8″ thick wall and the 10″ thick wall is that the diagonal FRP rebar 105 is 13 inches in length and spaced from the exterior corner of the intersection 106 by 7.5 inches. In both examples, FRP rebar is used. This provides significant advantages as compared to steel rebar. Steel rebar will stretch and yield, but FRP rebar will not stretch as much and has greater bond strength. The FRP rebar may be comprised of basalt fiber, carbon fiber, aramid fiber, glass fiber, or any combination of the foregoing or their functional equivalents.

[0018] In an alternate embodiment, the diagonal GFRP rebar 105 may instead be positioned so that it intersects with the two primary rebars 101 at the location where those primary rebars 101 intersect, as shown in FIG. 2.

[0019] To use the above inventive placement of straight rebar reinforcements instead of curved rebar, a user can start by placing an outside corner concrete form 111 along a foundation to form a first and second wall. The first and second walls form a rectangular intersection. Then, the user will place a plurality of vertical reinforcement poles 107 in the foundation, a distance away from the outside concrete form as shown in FIG. 2. A plurality of horizontally disposed straight rebar 101, 102 is then attached to the vertical reinforcement poles.

[0020] Next, an FRP rebar 105 may be placed in a manner that it intersects with the horizontally disposed rebar 101, 102 in the first and second walls at a 45-degree angle to each. The rebar 105 has a length such that a first end of the rebar 108 extends outside the rectangular intersection and into the first wall. A second end of the rebar 109 extends outside the rectangular intersection and into the second wall. The rebar is connected to the horizontally disposed rebar 101, 102 with ties or some other connection means 110. Then a concrete cover 112 is placed a distance away from the horizontally disposed rebar 101, opposite the concrete form 111. Finally, the concrete is poured between the concrete form 111 and concrete cover 112 to form the first and second walls.

[0021] In the disclosed embodiments the rebar may comprise #3 (GFRP rebar, such as MST-BAR® available from B&B FRP Manufacturing Inc.

[0022] Multiple vertical spacings of the GFRP rebar may be made, depending on how tall and long the wall is and the soil load against the wall, as shown by the following:

TABLE-US-00001 8-inch flat basement walls analyzed as rectangular plates with simply supported edges Wall height = 8 ft Backfill height = 7 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density 30 /ft 45 /ft 60 /ft MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  8 * 91 * 60 * 52 1.5 12 * 56 * 37 * 28 2 16 * 44 * 29 * 22 3 24 * 40 * 26 * 20 4 32 * 38 * 25 * 19 *One #3 horizontal bar within 12 inches from the top of wall and one #3 horizontal bar placed at mid-height on the wall. Wall height = 8 ft Backfill height = 7 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density 30 /ft 45 /ft 60 /ft MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  8 * 69 * 46 37 34 1.5 12 * 42 * 28 37 21 2 16 * 34 * 22 41 17 3 24 * 30 * 20 * 15 4 32 * 29 * 29 * 14 *One #3 horizontal bar within 12 inches from the top of wall and two #3 horizontal bar placed at mid-height on the wall. Wall height = 9 ft Backfill height = 8 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density wall 30 /ft 45 /ft 60 /ft length, MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  0 * 49 * 26 24 1.3   13.5 * 30 * 200 26 15 2 18 * 24 * 16 29 12 3 27 * 21 * 14 * 10 4 36 * 20 * 13 * 10 *One #3 horizontal bar within 12 inches from the top of wall and two #3 horizontal bar placed at third points on the wall. Wall height = 9 ft Backfill height = 9 ft Bar location= 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density wall 30 /ft 45 /ft 60 /ft length, MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  0 * 49 * 26 24 1.5   13.5 * 30 * 20 26 15 2 18 * 24 * 16 29 12 3 27 * 21 * 14 * 10 4 36 * 20 * 13 * 10 *One #3 horizontal bar within 12 inches from the top of wall and two #3 horizontal bar placed at third points on the wall. indicates data missing or illegible when filed

TABLE-US-00002 10-inch flat basement walls analyzed as rectangular plates with simply supported edges Wall height = 8 ft Backfill height = 7 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density 30 /ft 45 /ft 60 /ft MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  8 * 120 * 80 * 60 1.5 12 * * 49 * 36 2 16 * * 39 * 3 24 * 53 * 35 * 36 4 32 * * 33 * 25 *One #3 horizontal bar within 12 inches from the top of wall and one #3 horizontal bar placed at mid-height on the wall. Wall height = 8 ft Backfill height = 8 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density 30 /ft 45 /ft 60 /ft MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  8 * 92 * 61 * 46 1.5 12 * 56 * 38 * 28 2 16 * 40 * 30 * 22 3 24 * 40 * 27 * 20 4 32 * 38 * * 19 *One #3 horizontal bar within 12 inches from the top of wall and one #3 horizontal bar placed at mid-height on the wall. Wall height = 8 ft Backfill height = 8 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density wall 30 /ft 45 /ft 60 /ft length, MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  9 * 92 * 61 * 46 1.3   13.5 * 56 * 37 * 28 2 18 * 49 * 30 * 22 3 27 * 40 * 27 * 20 4 36 * 38 * 25 * 19 *One #3 horizontal bar within 12 inches from the top of wall and two #3 horizontal bar placed at third points on the wall. Wall height = 9 ft Backfill height = 8 ft Bar location = 1.5 inches clear cover from tension (interior) face Soil Equivalent Unit Density wall 30 /ft 45 /ft 60 /ft length, MST-BAR #3spacing. MST-BAR #3 spacing. MST-BAR #3 spacing. wall ratio ft Horizontal Vertical Horizontal Vertical Horizontal Vertical 1  9 * * 54 * 40 1.5   13.5 * 50 * 33 * 25 2 18 * 40 * 26 * 20 3 27 * 36 * 24 * 18 4 36 * 34 * 22 * 17 *One #3 horizontal bar within 12 inches from the top of wall and two #3 horizontal bar placed at third points on the wall. indicates data missing or illegible when filed

[0023] Alternatively, these spacings for the vertical rebar may be utilized for walls with heights of 8, 9 or 10 ft.:

TABLE-US-00003 MAX BACKFILL HT. WALL LENGTH VERT. BAR SPACING 7 FT <8 FT 4EQ @ 48″ O.C.  8 FT-12 FT 4EQ @ 36″ O.C. 12 FT+ 4EQ @ 24″ O.C. 8 FT <8 FT 4EQ @ 42″ O.C.  8 FT-12 FT 4EQ @ 30″ O.C. 12 FT-24 FT 4EQ @ 20″ O.C. 24 FT+ 4EQ @ 18″ O.C. 8 FT <9 FT 4EQ @ 42″ O.C.  9 FT-15 FT 4EQ @ 24″ O.C. 15 FT+ 4EQ @ 18″ O.C. 9 FT <9 FT 4EQ @ 32″ O.C.  9 FT-15 FT 4EQ @ 18″ O.C. 15 FT-27 FT 4EQ @ 16″ O.C. 27 FT+ 4EQ @ 12″ O.C. 9 FT <10 FT  4EQ @ 24″ O.C. 10 FT-15 FT 4EQ @ 12″ O.C. 15 FT+ 4EQ @  9″ O.C. 10 FT  <10 FT  4EQ @ 18″ O.C. 10 FT-15 FT 4EQ @ 12″ O.C. 15 FT-20 FT 4EQ @  9″ O.C. 20 FT+ 4EQ @  6″ O.C.

[0024] Those of skill in the art will understand that various details of the invention may be changed without departing from the spirit and scope of the invention. Furthermore, the foregoing description is for illustration only, and not for the purpose of limitation, the invention being defined by the claims.

[0025] While the invention has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as illustrative and not restrictive in character, it being understood that only illustrative embodiments thereof have been show and described and that all changes and modifications that are within the scope of the following claims are desired to be protected.

[0026] All references cited in this specification are incorporated herein by reference to the extent that they supplement, explain, provide a background for or teach methodology or techniques employed herein, including Building Code Requirements for Structural Concrete (ACT 318-14), and Commentary on Building Code Requirements for Structural Concrete (ACT 318R-14) and Code Requirements for Residential Concrete and Commentary, all published by the American Concrete Institute (“ACT”).