PRECAST FOUNDATION COLUMN ASSEMBLY FOR SUPPORTING A BUILDING FRAME POST

Description

This application claims the benefit under 35 U.S.C. 119(e) of U.S. provisional application Ser. No. 63/632,253, filed Apr. 10, 2024.

FIELD OF THE INVENTION

The present invention relates to a precast foundation column assembly for supporting a post of a building frame thereon relative to ground.

BACKGROUND

In the construction of a post-frame building, it is common practice to form the frame of a plurality of wooden frame posts having their bottom ends set on foundation pads within respective holes in the ground such that the frame posts protrude above the ground. Roof trusses and wall framing members (also known as girts) are then connected between the protruding portions of the wooden frame posts to complete the frame of the building. To prevent degradation of the bottom ends of the wooden frame posts, at least the lower portion of the wooden frame posts should be treated.

Alternatively, U.S. Pat. No. 6,964,139 by Perma-Column, Inc. discloses an arrangement in which the wooden frame posts are replaced with a two-part post having an upper wooden portion and a lower concrete portion. The lower concrete portion is received on a separate foundation pad within a respective hole in the ground in the usual manner. To prevent the concrete post from lifting from the ground as a result of seasonal freeze and thaw of the ground, a transverse anchor pin must be inserted through the bottom of the concrete post and additional concrete must be poured on site to bond with the anchor pin.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided a foundation column assembly for supporting a wooden post of a building frame thereon relative to ground, the assembly comprising:

• • a column comprising a unitary concrete body extending longitudinally between a top end and a bottom end of the column;
  • a bracket arrangement at the top end of the column, the bracket arrangement being arranged to be fastened to the wooden post of the building; and
  • at least one connecting rod connected to the bracket arrangement and extending longitudinally into the unitary concrete body of the column;
  • wherein the unitary concrete body of the column comprises:
    • (i) an upper portion adjacent the bracket arrangement at the top end of the column in which the upper portion has cross-sectional dimensions which are equal to or less than corresponding dimensions of the wooden post; and
    • (ii) a lower portion below the upper portion and adjacent to the bottom end of the column in which the lower portion has cross-sectional dimensions which are greater than the cross-sectional dimensions of the upper portion.

By providing a precast concrete column that supports a wooden frame post thereon, the wooden frame post is separated from direct contact with the ground to minimize degradation of the wooden frame post over time. The further arrangement of the precast concrete column with a lower portion of increased dimension relative to the upper portion provides the function of a footing integral with the column that increases the load bearing capacity of the column without additional foundation pads being required to be inserted into the holes in the ground below the columns. Furthermore, the increased dimension of the lower portion relative to the upper portion acts to prevent uplift of the column in response to seasonal freeze and thaw cycles, within the need for a transverse anchor pin and additional poured concrete on site into the hole in the ground according to the prior art arrangement described above.

Preferably the upper portion spans a majority of a length of the column.

The lower portion preferably defines a footing which protrudes radially relative to the upper portion about a full circumference of the lower portion.

According to the illustrated embodiment, the cross-sectional dimensions of the lower portion are at least 50% greater than the cross-sectional dimensions of the upper portion.

Preferably said at least one connecting rod extends into the lower portion of the column. Each one connecting rod may include (i) a main rod portion extending continuously between the bracket and the lower portion of the column, and (ii) a transverse portion extending transversely to a longitudinal direction of the column within the lower portion of the column. The transverse portion is preferably spaced below a top end of the lower portion of the column.

The bracket arrangement may be further arranged for use with a plurality of wood screws for penetration into the wooden post, in which the bracket comprises a pair of plates locating a plurality of fastener apertures therein arranged to cooperate with the wood screws to fasten the bracket arrangement to the wooden post.

According to a second aspect of the present invention there is provided a method of supporting a wooden post of a building frame thereon relative to ground, the method comprising:

• • providing a column assembly comprising (i) a column comprising a unitary concrete body extending longitudinally between a top end and a bottom end of the column, (ii) a bracket arrangement at the top end of the column, and (iii) at least one connecting rod connected to the bracket arrangement and extending longitudinally into the unitary concrete body of the column, wherein the unitary concrete body of the column comprises (a) an upper portion at the top end of the column having cross-sectional dimensions which are equal to or less than corresponding dimensions of the wooden post and (b) a lower portion below the upper portion and adjacent to the bottom end of the column in which the lower portion has cross-sectional dimensions which are greater than the cross-sectional dimensions of the upper portion;
  • inserting the column assembly into a hole formed in to the ground such that the bracket assembly protrudes from the ground;
  • fastening the wooden post to the column assembly; and
  • backfilling the hole with backfilling material such that the backfilling material surrounds at least the lower portion and part of the upper portion of the column within the hole in the ground.

The method may further include providing a plurality of wood screws for penetration into the wooden post, and fastening the wood screws into the wooden post through fastener apertures in the bracket arrangement to fasten the bracket arrangement to the wooden post.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the invention will now be described in conjunction with the accompanying drawings in which:

FIG. 1 is perspective view of a first embodiment of the precast foundation column assembly according to the present invention;

FIG. 2 is a side elevational view of the precast foundation column assembly according to the first embodiment of FIG. 1;

FIG. 3 is a front elevational view of the precast foundation column assembly according to the first embodiment of FIG. 1;

FIG. 4 is a top view of the precast foundation column assembly according to the first embodiment of FIG. 1;

FIG. 5 is a side elevational view of the precast foundation column assembly according to a second embodiment;

FIG. 6 is a front elevational view of the precast foundation column assembly according to the second embodiment of FIG. 5;

FIG. 7 is a top view of the precast foundation column assembly according to the second embodiment of FIG. 5;

FIG. 8 is a side elevational view of the precast foundation column assembly according to a third embodiment;

FIG. 9 is a front elevational view of the precast foundation column assembly according to the third embodiment of FIG. 8; and

FIG. 10 is a top view of the precast foundation column assembly according to the third embodiment of FIG. 8.

In the drawings like characters of reference indicate corresponding parts in the different figures.

DETAILED DESCRIPTION

Referring to the accompanying figures there is illustrated a foundation column assembly generally indicated by reference numeral 10. The assembly 10 is particularly suited for use in a post-frame building 12 as described in the following.

A typical post frame building 12 includes a building frame having a plurality of wooden frame posts 14 primarily supported at spaced apart positions about the perimeter of the building. According to the present invention, each frame post 14 is supported relative to ground 16 by a respective assembly 10 as described in the following. A generally cylindrical hole 18 is first formed in the ground to receive the assembly 10 therein such that the assembly is primarily located below grade while a portion of the assembly 10 protrudes above ground for mounting the bottom end of the respective frame post 14 thereon at a location spaced above the ground. Roof trusses are typically connected between the posts at opposing sides of the building frame. Adjacent posts are also connected by horizontal frame members 20 referred to as girts that extend along the exterior of rows of posts for supporting exterior sheathing 22 thereon to form the exterior walls of the building. Additional exterior finishing material can be supported on the exterior side of the sheathing and on the roof trusses to form the exterior walls and roof of the building.

Although various embodiments of the foundation column assembly 10 are shown in the accompanying figures, the features in common with the various embodiments will first be described herein.

Each foundation column assembly 10 generally includes (i) an upright column 24 comprising a unitary concrete body extending in a longitudinal direction between a top end 26 and a bottom end 28 of the column, (ii) a bracket 30 mounted at the top end 26 of the column 24 for securing the bottom end of the wooden frame post 14 thereon, and (iii) a plurality of connecting rods 32 fixed to the bracket 30 to extend into the concrete body of the column 24 for connecting the bracket 30 to the column 24 and for reinforcing the concrete column. Each column 24 includes an upper portion 34 defining the top end of the column and a lower portion 36 below the upper portion which extends to the bottom of the column. The upper portion 34 mounts the bracket 30 thereon and has a cross-sectional shape and cross-sectional dimensions perpendicular to the longitudinal direction of the column which are approximately equal to the corresponding shape and dimensions of the wooden frame post 14. The lower portion 36 below the upper portion is increased in dimension relative to the upper portion to define a cylindrical shaped footing that is integral with the upper portion. The increased dimension of the lower portion 36 of the column increases the load bearing capacity of the column.

The bracket 30 of each assembly 10 is formed of rigid plate metal to be generally U-shaped. More particularly, the bracket includes a base plate 38 having rectangular dimensions which are similar to the cross-sectional shape and dimensions of the wooden frame post 14 above and the upper portion 34 of the concrete column 24 below. The bracket also includes two side plates 40 extending perpendicularly upward from opposing ends of the base plate 38 so as to be parallel and spaced apart from one another by a distance that is approximately equal to a corresponding distance of the bottom end of the frame post received between the side plates.

A plurality of fastener apertures are located in each side plate 40 within an upper group 42 of fasteners in proximity to the top end of the side plate and a lower group 44 of fasteners that are spaced below the upper group 42 towards the bottom end of the side plate. Each of the fastener apertures is suitably sized for receiving a wood screw inserted therethrough for threaded penetration into the wooden frame post received between the side plates while retaining the head of the screw against an outer surface of the side plate. In the illustrated embodiment, the fastener apertures have a diameter of 9/32 of an inch and each group of fasteners comprises three rows of three fastener apertures in which the apertures in each row are staggered and offset laterally relative to the apertures of the adjacent row(s).

The bracket 30 further includes a stiffener plate 46 comprising a plate of metal which is thicker than the metal forming the base plate 38 and side plates 40 and has dimensions similar to the base plate. The stiffener plate 46 is secured immediately below the base plate 38 by welding along all four edges to corresponding edges of the base plate 38.

The upper portion 34 of the concrete column 24 has a rectangular cross-section with cross-sectional dimensions oriented perpendicularly to the longitudinal direction that are approximately equal to corresponding dimensions of the wooden frame post to be mounted within the bracket 30. The upper portion spans the majority of the height of the column between the junction of the upper and lower portions at an intermediate portion of the column to the top end of the column. In the illustrated embodiment, the upper portion spans a height of approximately 5 feet; however, the upper portion may have a height between 2 feet and 8 feet in further embodiments for example.

The lower portion 36 of the concrete column is cylindrical in shape while having a height which is much less than the height of the upper portion. In the illustrated embodiments, the lower portion has a height of approximately 6 inches; however, the lower portion may have a height between 4 inches and 6 feet in further embodiments for example. The diameter of the lower portion is much greater than the corresponding dimensions of the upper portion such that the lower portion protrudes radially outward relative to the upper portion about the full circumference of the column. In the illustrated embodiment, the lower portion has a radius of 12 inches. In this instance, the cross-sectional dimensions of the lower portion within a plane perpendicular to the longitudinal axis of the column are greater than corresponding dimensions of the upper portion and the wooden post above.

A set of four connecting rods 32 are provided to span the majority of the length of the column in the longitudinal direction. Each connecting rod is a metal rod welded to the stiffener plate 46 at the bottom of the bracket to form a continuous and unitary metal body together with the bracket. In the illustrated embodiment, the four connecting rods are arranged at the corners of a rectangular pattern such that each connecting rod is associated with a respective corner of the rectangular cross-sectional shape of the upper portion of the column while being spaced inwardly from both of the adjacent sides so that each of the connecting rods is fully surrounded by the concrete material of the column.

Each connecting rod 32 includes a main rod portion 48 which extends linearly from the bracket at the top end of the column across the full length of the upper portion of the column to terminate at an intermediate location within the lower portion of the column. The main rod portion is thus longer than the upper portion of the column. Each connecting rod also includes a transverse portion 50 which is bent perpendicularly relative to the main rod portion so as to be generally horizontal in orientation within the lower portion of the concrete column. In the illustrated embodiment, the transverse portion 50 is centrally located between top and bottom ends of the lower portion of the column. The connecting rods are arranged in pairs with each transverse portion 50 extending from the respective rod portion 48 towards the other connecting rod of the associated pair. The two connecting rods of each associated pair thus collectively form a generally U-shaped arrangement with the transverse portions 50 thereof being located closely alongside one another.

Each assembly 10 is formed by initially forming the bracket 30 from metal plate material and attaching the connecting rods 32 in the desired pattern. The upper and lower portions of the concrete column are then formed together to fully surround the connecting rods. Once the concrete material has cured, the finished assembly 10 can be transported from the manufacturing location of the assembly to a building site where the assembly 10 will be used in the construction of a building.

At the building site, a hole is formed in the ground at the location of each frame post of the frame of the building. Each precast foundation column assembly 10 is then placed in the respective hole in the ground so that the lower portion of the column is abutted with the bottom end of the hole. A wooden frame post 14 is then attached to each assembly 10 by inserting the bottom end of the frame post between the side plates 40 in abutment with the base plate 38 such that the cross-sectional shape of the frame post is substantially continuous with the upper portion of the column 24 below. Wood screws are then inserted through the fastener apertures in the upper and lower groups 42 and 44 while penetrating and threading the wood screws into the wooden material of the post 14 to secure the post relative to the assembly 10. A different number of screws can be used depending upon the size and loading of the wooden post. The holes in the ground are then backfilled with suitable backfill material, for example stone aggregate material or soil, and the backfill material is compacted about the portion of each assembly 10 located below grade. The holes are typically formed in the ground at a depth that places the bracket 30 spaced slightly above ground level resulting in the lower portion of the column being fully embedded in the ground while a majority of the upper portion of the column is embedded in the ground, but with the top end of the column protruding slightly above ground.

Turning now to FIGS. 2 through 4, in the instance of a post formed by three plies of 2 inch×8 inch dimensional lumber, the resulting wooden frame post has cross-sectional dimensions of approximately 7 inches by 4⅝ inches. The upper portion of the concrete column corresponds to the dimension of the lumber in one direction and the combined dimensions of the lumber with the side plates of the bracket overlapping each side of the wooden frame post in the other direction such that the overall dimensions of the upper portion of the concrete column in this instance is 7 inches×5⅛ inches. The corresponding lower portion in this embodiment has a diameter of approximately 12 inches.

Turning now to FIGS. 5 through 7, in the instance of a post formed by four plies of 2 inch×8 inch dimensional lumber, the resulting wooden frame post has cross-sectional dimensions of approximately 7 inches by 6⅛ inches. The upper portion of the concrete column corresponds to the dimensions of the lumber in one direction and the combined dimensions of the lumber with the side plates overlapping each side of the wooden frame post in the other direction such that the overall dimensions of the upper portion of the concrete column in this instance is 7 inches×6 ⅝ inches. The corresponding lower portion in this embodiment has a diameter of approximately 12 inches.

Turning now to FIGS. 8 through 10, in the instance of a post formed by five plies of 2 inch×8 inch dimensional lumber, the resulting wooden frame post has cross-sectional dimensions of approximately 7 inches by 7⅝ inches. The upper portion of the concrete column corresponds to the dimensions of the lumber in one direction and the combined dimensions of the lumber with the side plates overlapping each side of the wooden frame post in the other direction such that the overall dimensions of the upper portion of the concrete column in this instance is 7 inches×8 ⅛ inches. The corresponding lower portion in this embodiment has a diameter of approximately 14 inches.

In the above illustrated embodiments, the cross-sectional area of the lower portion is typically between 1.5 and 5 times greater than the cross-sectional area of the upper portion, and more preferably between 2 and 3 times greater than the cross-sectional area of the upper portion. As noted above, the increased dimension of the lower portion 36 of the column relative to the upper portion 34 increases the load bearing capacity of the column.

Since various modifications can be made in the invention as herein above described, and many apparently widely different embodiments of same made, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.