Patent Application
20090178353
The present invention generally relates to a method and apparatus for setting building support columns within a foundation. The present invention more particularly relates to a method and apparatus which provides a secure footing for a support column, where the column may be installed after a concrete floor has been completed rather than the current practice of installing the column and pouring concrete around the column.
It is known in the construction industry to set vertical columns, such as steel columns typically utilized in the construction of various structures, within concrete footings. One known method of preparing the footing for a column is to set a group (usually four) of L-shaped anchor bolts within a first concrete footing member, with threaded ends of the anchor bolts extending above the top of the first footing member, where a nut is disposed on the threads of each anchor bolt. The first concrete footing member typically has steel reinforcement. A flat slab (or section of slab) comprising the floor of the structure is poured after the L-shaped bolts for each of the columns of the structure have been set within a column's respective first footing member. However, forms are constructed around each column footing to isolate the column footing from the slab, forming an area hereinafter referred to as the “blocked out area.” The first footing member and the group of upwardly facing anchor bolts within the blocked out area remain exposed after the slab has been poured until later in the construction process as described below.
Once the first concrete footing member around each group of L-shaped anchor bolts has cured, columns having a baseplate attached to the bottom end of each column are attached to the upwardly extending ends of the L-shaped anchor bolts at each footing location. Typically, nuts are first made up on the threads of the L-shaped anchor bolts prior to placing the baseplate and column over the bolts such that the baseplate comes to rest against this first group of nuts as the baseplate is disposed on the anchor bolts and the column set in a vertical orientation. A second nut is thereafter made up on each anchor bolt thereby securing the baseplate to the footing.
Upper structural members or roof members are thereafter attached to the columns. The column and baseplate are leveled as necessary and the space between the first concrete footing member and the bottom of the baseplate is filled in with grout known as “dry pack.” An inspection of the column footing is normally required after the baseplate has been grouted.
Once the grout underneath the baseplate has adequately cured, concrete is typically poured into the blocked out area overlying the first footing member, thereby forming a second layer of concrete around the column base and footing. The pouring of the cement slurry in the blocked out area around the column usually occurs after the roof or upper floor structural members have been set in place, often making it difficult to bring large equipment in to pour the cement slurry in the blocked out area. The second layer of concrete surrounds the steel column and completely covers the baseplate and the upwardly extending ends of the L-shaped bolts. The level of the second layer of concrete is generally flush with the surrounding concrete slab.
The method described above for affixing columns to a concrete foundation has some disadvantages. For example, the second layer of concrete in the blocked out area surrounding the columns is visually distinct from the rest of the slab. The boundary lines created by the forms between the surrounding slab and the second concrete layer are clearly visible. Moreover, because of the time span between the pouring of the slab and the second concrete layer, there is a color variation between the concrete slab and the second concrete layer. In structures such as a warehouse, where the slab is not covered with floor coverings, the visible difference between the slab and the concrete adjacent to each column are not as aesthetically pleasing as for a slab surface constructed with a single pour.
As another disadvantage, the pouring of the second concrete layer in the blocked out area requires mobilizing equipment for mixing, delivering, and pouring the concrete. The mobilization of the equipment can be further complicated because of the addition of new members to the structure, such as wall members or roof members, which reduce access of equipment to the blocked out area. It is often necessary to utilized wheel barrows to transport concrete slurry to the blocked out area, resulting in an increase in the time required to pour the second concrete layer.
As another disadvantage, the known system can result in delays while waiting on inspections or waiting for equipment to arrive. For example, an inspection of the dry pack around the bottom of the column is normally required before the second concrete layer can be poured.
An apparatus and method which allows the pouring of the concrete slab and the second concrete layer around the column footings in a single pour would eliminate or reduce the visible differences between the slab and the second concrete footing, reduce mobilization time for concrete equipment, and reduce waiting time required for inspections or equipment. An apparatus and method which enables the baseplate to be leveled without grout would eliminate the time involved in placing the grout, allowing it to set and waiting for inspection.
The present invention is directed to an apparatus and method which meet the needs identified above for affixing support columns to a foundation. An embodiment of the apparatus comprises a column support footing for receiving and supporting the bottom end of a vertical column of a structure after a concrete floor is poured. The use of embodiments of the column support footing allows an entire concrete floor or slab to be poured before the placement of support columns, which facilitates the construction process and eliminates the need to pour concrete immediately around the base of each column according the known practice.
The column support footing may comprise a column support sleeve which may be integral to or attached to a generally horizontal baseplate having an upward facing side and a groundward facing downward side. The column support sleeve is disposed on the upward facing side of the baseplate. The column support sleeve has an upwardly facing open end for receiving the bottom end of the column. Extending from the downward side of the column support sleeve or the baseplate is an anchor member. A portion of the anchor member is set within a concrete footing member, where the top surface of the concrete footing member is below the baseplate. A second concrete footing member, such as the floor of the structure under construction, is poured after the first concrete footing member has cured around a portion of the anchor member, and the bottom surface of the second footing member overlies at least a portion of the top surface of the first footing member. The second footing member provides lateral support to the column support sleeve, and the level of the second footing member may be configured such that it is flush with the top of the column support sleeve; that is, where the second footing member comprises a floor, the top of the column support sleeve is flush with the surface of the floor. The column may then be placed within the column support sleeve and attached to prevent uplift of the column from the column support sleeve.
Embodiments of this apparatus, and the methods of utilizing the embodiments, allow the pouring of a concrete floor immediately around the column support apparatus without the need to block out an isolated area as currently practiced. When a column is set within the apparatus, the concrete floor is nearly directly adjacent to the column, eliminating the need for an additional pour around the column as currently practiced.
These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings.
Referring now specifically to the drawings,
Once the first concrete footing member 104 has sufficiently cured around anchor bolts 102, a column 110 comprising a baseplate 112 may be set upon the anchor bolts, with the baseplate supported by the nuts previously made up on the bolts. A second set of nuts 114 is thereafter made up on anchor colts 102 to secure the baseplate 112 and attached column 110. After the columns 110 for the structure are installed, other structural members for the building are typically installed, such as roof members, trusses, walls, etc., with level adjustments made to each column 110 by adjusting the nuts 114 below the baseplate 112. Once the column 110 has been leveled as necessary, grout 116 in the form of dry pack is disposed in the spaced defined by the bottom of the baseplate 112 and the top of the first concrete footing member 104.
Once the columns 110 have been placed, concrete is poured in the blocked area around the column support footing forming thereby forming secondary slab 118 around each column 110. As indicated by
Once the first concrete footing member 204 has sufficiently cured around anchor bolts 202, a generally horizontal baseplate 212 is set over the anchor bolts, with the bottom of the baseplate supported by nuts 214 which have been made up on the threads of the anchor bolts. A second set of nuts 214 are attached to the anchor bolts 202 and made up against the upward facing side 220 of the baseplate 212. The baseplate 212 comprises a column support sleeve 222 on the upward facing side 220 where the column support sleeve has an upwardly facing open end for receiving the bottom end of a column 210. As shown in
Once the baseplate 212 and column support sleeve 222 have been set on the anchor bolts 202, the baseplate 212 is leveled as necessary and grout 216 in the form of dry pack is disposed in the spaced defined by the bottom of the baseplate 212 and the top of the first concrete footing member 204. Once the grout 216 is set, concrete floor 208 is poured, including the pouring of cement over the baseplate 212 and around the column support sleeve 222, such that the concrete overlies all or a portion of the first concrete footing member 204 in which the anchor bolts 202 have been set, and the cement surrounds column support sleeve 222. It is to be appreciated that concrete floor 208 is poured such that it is immediately adjacent to where the base of column 210 will eventually be placed, rather than blocked off as in the prior art method described above, such that the concrete floor 208 provides lateral support to the column support sleeve 222, and thus will support column 210 when it is placed within the column support sleeve. Concrete floor 208 may thus be considered to be a second concrete footing member. It is also to be appreciated that a temporary cap or insert should be placed within column support sleeve 222 to prevent concrete from spilling or falling inside the sleeve.
Once the concrete floor 208 has cured around the column support sleeve 222, the bottom end of column 210 may be inserted into the column support sleeve. In order to prevent uplift of the column 210, attachment means are utilized for attaching the column support sleeve 222 to the bottom end of the column 210. For example, as best shown in
The column support apparatus 330 further comprises at least one anchor member 302 extending downwardly from the downward side of the baseplate member 312 or, alternatively, from the column support sleeve 322. The anchor member 302 may be in the form of an “L” to prevent uplift of the anchor from the concrete footing. Although four anchor members 302 are depicted in
Column support footing 300 further comprises a concrete footing member 304 into which the anchor members 302 of column support apparatus 330 are set. Concrete footing member 304 typically comprises steel reinforcement members 306. The concrete footing member 304 encases a portion of the anchor members 302, but the top surface 332 of the concrete footing member is below the downward facing side of the baseplate member 312, as shown in
Once the first concrete footing member 304 has sufficiently cured around anchor members 302, concrete floor 308 is poured, including the pouring of cement over the baseplate member 312 and around the column support sleeve 322, such that the concrete floor 308 directly overlies all or a portion of the first concrete footing member 304 in which the anchor members 302 have been set, and the cement surrounds column support sleeve 322. It is to be appreciated that concrete floor 308 is poured such that it is immediately adjacent to where the base of column 310 will eventually be placed, rather than blocked off as in the prior art method described above, such that the concrete floor 308 provides lateral support to the column support sleeve 322, and thus will support column 310 when it is placed within the column support sleeve. Concrete floor 308 may thus be considered, with respect to the column 310, as a second concrete footing member which overlies all or a portion of the first concrete footing member 304. It is also to be appreciated that a temporary cap or insert should be placed within column support sleeve 322 to prevent concrete from spilling or falling inside the sleeve.
Once the concrete floor 308 has cured around the column support sleeve 322, the bottom end of column 310 may be inserted into the column support sleeve. In order to prevent uplift of the column 310, attachment means are utilized for attaching the column support sleeve 322 to the bottom end of the column 310. For example, retainer plates 324 may welded to both the column support sleeve and to the bottom end of column 310, or the column may be welded directly to the column support sleeve. The remaining space between the inside of the column support sleeve 322 and the bottom of the column 310 may be filled as desired with concrete or grout.
It is to be appreciated that the embodiment 300 of the column support footing shown in
As shown in
The embodiments of the disclosed apparatus may be utilized in a method of setting a vertical column within a footing which allows the pouring of a concrete floor prior to the installation of the columns. The method has the further advantage of eliminating a subsequent concrete pour around the base of a column to cover the column base and footing.
An embodiment of the method, which may utilize embodiments of the apparatus shown in
Once the cement of the concrete floor 208 adequately sets, the bottom end of column 210 may be inserted into column support sleeve 222 and secured with fastening or attachment means, such as welding or threaded fasteners.
An embodiment of the method, which may utilize embodiments of the apparatus shown in
While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. For example, the size, shape, and/or material of the various components may be changed as desired. Thus the scope of the invention should not be limited by the specific structures disclosed. Instead the true scope of the invention should be determined by the following claims.
