BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of a connection formed in accordance with the present invention.
FIG. 2 is a top plan view of the connector of the present invention.
FIG. 3 is a front elevation view of the connector of the present invention.
FIG. 4 bottom plan view of the connector of the present invention.
FIG. 5 is a back elevation view of the connector of the present invention.
FIG. 6 is a left side elevation view of the connector of the present invention.
FIG. 7 is a right side elevation view of the connector of the present invention.
FIG. 8 is a cross-section view of a connection formed in accordance with the present invention.
FIG. 9 is a cross-section view of the column and connector of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
As best shown in FIGS. 1 and 8, the present invention is a column holdown connection 1 in a building 2. The connection 1 comprises, basically, an underlying structural member 3, an anchor 4, a substantially vertical metal column 6, and a holdown connector 8. The anchor 4 is restrained by the underlying structural member 3. The anchor 4 has an attachment end 5 protruding above the underlying structural member 3. The substantially vertical metal column 6 has a bottom end 7 supported by the underlying structural member 3. The holdown connector 8 has a back member 9 and a seat member 10. The back member 9 is fastened to the column 6 with a plurality of bolts 11 and a plurality of screws 12. The seat member 10 is restrained by the attachment end 5 of the anchor 4.
As best shown in FIGS. 1 and 8, preferably the underlying structural member 3 is a foundation 3. More preferably, the the foundation 3 is cementitous. In the most preferred embodiment, the foundation 3 is concrete reinforced with steel rebar. Alternatively, the underlying structural member 3 could be the floor 3 of an upper storey. In such a case, the anchor 4 could be restrained through a second holdown connector 8, an arrangement common in floor-to-floor connections.
As best shown in FIGS. 1 and 8, the anchor 4 is preferably an anchor bolt 4, specifically a ⅞ inch anchor bolt. Most preferably, the anchor is a bent steel bolt 3 embedded in a ferroconcrete foundation 3.
As best shown in FIGS. 2 and 4, preferably the seat member 10 of the holdown connector 8 is formed with an anchor opening 13 through which the attachment end 5 of the anchor 4 passes. The attachment end 5 of the anchor 4 preferably has helical threads 14 and a nut 15 is threaded onto the helical threads 14, thereby restraining the attachment end 5 against the seat member 10. Alternatively, the attachment end 5 of the anchor 4 could be welded to the holdown connector 8 or otherwise fixed.
As best shown in FIGS. 1 and 8, the column 6 is preferably an I-beam 6 with a central, substantially planar web member 16 having a first side 17 and a second side 18, a first substantially planar side member 19 and a second substantially planar side member 20. Preferably, the first side member 19 and the second side member 20 are generally perpendicular to the web member 16 and extend beyond both the first side 17 and the second side 18 of the web member 16 to create a pair of back-to-back channels 21. Alternatively, the column 6 could be a hollow, tubular column 6 or even a thick, solid block 6.
As best shown in FIG. 8, preferably the column 6 is formed with a plurality of bolt openings 22 in the web member 16 adjacent the bottom end 7. The holdown connector 8 is preferably formed with a plurality of bolt openings 23 in the back member 9. And, preferably, the plurality of bolts 11 passes through the plurality of bolt openings 23 in the back member 9 of the holdown connector 8 and through the plurality of bolt openings 22 in the column 6.
As best shown in FIGS. 8 and 9, the bolt openings 22 in the column 6 are preferably slotted openings 22, each with a horizontal diameter 33 and a vertical diameter 24, the horizontal diameter 33 being greater than the vertical diameter 24. This would allow for horizontal adjustment of the holdown connector 8 relative the column 6 and the anchor 4. Most preferably, the horizontal diameter 33 is 1.25 inches and the vertical diameter 24 is 0.8125 inches.
As best shown in FIGS. 3 and 5, preferably the bolt openings 23 in the back member 9 of the holdown connector 8 are round, so that there is as little play as possible between the bolts 11 and the bolt openings 23.
As best shown in FIGS. 3 and 5, the back member 9 of the holdown connector 8 is preferably formed with a plurality of screw openings 25. Preferably, the plurality of screws 12 passes through the plurality of screw openings 25 in the back member 9 of the holdown connector 8 and into the web member 16 of the column 6. Alternatively, holes could be drilled through either the holdown connector 8, the column 6, or both at the time of installation, either with a drill bit or with self-drilling screws 12. The screws 12 of the plurality of screws 12 are preferably self-drilling screws 12, whether or not holes are prepared in the holdown connector 8 and the column 6. Preferably, the screws 12 of the plurality of screws 12 are also self-tapping screws 12. Most preferably, the screws 12 are #14 self-drilling screws.
As best shown in FIGS. 1 and 8, the bottom end 7 of the column 6 preferably rests on a substantially horizontal bottom plate 26, and the bottom plate 26 rests on the underlying structural member 3. Preferably, the bottom plate 26 is a channel 26 having two side members 27 and a bottom member 28, the two side members 27 embracing the bottom end 7 of the column 6. Alterntively, the column 6 could rest directly on the underlying structural member 3, with or without a discontinuous bottom plate 26 to either side of the column 6.
As shown in all the drawing figures, preferably,\ the back member 9 of the holdown connector 8 is substantially planar and substantially vertical. The seat member 10 of the holdown connector 8 preferably is substantially planar and substantially horizontal. These are essentially the simplest forms for the back member 9 and seat member 10 and therefore the easiest and most economical to manufacture and install.
As best shown in FIGS. 1, 2, 3 and 4, the back member 9 and the seat member 10 preferably are integrally joined, either by being bent out of the same sheet material or cast in the same mould, or by being welded together. Alternatively, the back member 9 and seat member 10 could be mechanically interlocked, either directly with each other or through other intervening parts of the holdown connector 8.
As best shown in FIG. 1, preferably the back member 9 and the seat member 10 are joined by a first side member 29 substantially orthogonal to both the back member 9 and the seat member 10. More preferably, the back member 9 and the seat member 10 are joined by a second side member 30, the second side member 30 being substantially orthogonal to both the back member 9 and the seat member 10. The first side member 29 and the second side member 30 preferably are substantially planar. Preferably, the back member 9 and the seat member 10 are generally rectangular while the first side member 29 and the second side member 30 are substantially triangular.
As best shown in FIG. 1, the back member 9 of the holdown connector 8 preferably fits entirely between the first side member 19 and the second side member 20 of the column 6. If the column 6 is, or has, a channel 21, it is advantageous to nest the holdown connector 8 within the channel 21 in order to come as close as possible to horizontally centering the holdown connector 8 to come as close as possible to perfectly concentric loading.
As best shown in FIG. 1, preferably the column 6 is a wall stud 6. In the most preferred form of the invention, the column is sufficiently narrow to fit within the space of a standard light frame wall, which is framed with nominal 2×4 wood studs when wood is the primary construction material.
As best shown in FIGS. 1 and 8, the bolt openings 22 in the web member 16 of the column 6 preferably are substantially vertically aligned. Most preferably, four bolt openings 22 in the web member 16 of the column 6 are used for the present invention. Most preferably, the lowest of these bolt openings is 6.25 inches from the bottom end 7 of the column 6 and the bolt openings 22 are 2.75 inches apart on center.
As best shown in FIGS. 1, 3 and 5, preferably the plurality of screws 12 are horizontally spaced to either side of the bolt openings 22 in the web member 16 of the column 6, in order to resist deflection and rotation.
The column 6 is preferably formed from steel, although any other material of sufficient strength and other requisite attributes could be used. Preferably, the holdown connector 8 is formed at least in part by cutting sheet steel. Cold forming connectors from sheet steel is common because of steel's malleability. The steel is preferably galvanized, but it can also be stainless, a more expensive alternative. The holdown connector 8 could be formed at least in part by casting metal. The most common metal for cast connectors is aluminum, because of its combination of light weight, resistance to corrosion, cost and the ease with which it is cast.
As best shown in FIG. 9, preferably the holdown connector 8 is formed with planar metal members 31 and the column 6 is formed with planar metal members 32 and the planar metal members 32 of the column 6 are thicker than the planar metal members 31 of the holdown connector 8.
Although the present invention is discussed as a holdown connection 1 basically comprising an underlying structural member 3, an anchor 4, a substantially vertical metal column 6, and a holdown connector 8, the holdown connector 8 of the present invention, like many prior art holdown connectors 8, could be oriented horizontally on a beam analogous to the metal column 6, anchored either to an adjacent structural member such as a wall or beam analogous to the underlying structural member 3. The connection 1 would be essentially the same, simply turned 90 degrees onto its side. The anchor 4 could be restrained through attachment to a second horizontally-oriented holdown connector 8, as in a vertical floor-to-floor tie connection.
Patent Application
20070245677
