The present disclosure relates to forms for pouring concrete columns of polygonal (e.g., square or rectangular) cross-section.
Pouring a round concrete column is a relatively simple matter typically entailing the use of a round paperboard tube as a form into which the concrete is poured. The paperboard tube is stripped from the column after the concrete hardens. On the other hand, pouring a square or rectangular column requires a form of more-complicated construction. In some cases, the form can comprise a round paperboard tube having additional elements inserted into the tube to define the desired non-round cross-sectional shape for the column to be formed. This type of form can be adequate for some applications, but may not have sufficient strength and stiffness for other applications.
High-strength forms made of steel panels and frames are available, but are relatively expensive and heavy, and can be complicated to assemble at the jobsite.
The present disclosure relates to a concrete form for pouring a column of polygonal cross-section, which can be constructed from predominantly non-metallic materials and yet can achieve high strength and stiffness, and which is also relatively simple to assemble at a jobsite. In accordance with one aspect of the present disclosure, a concrete form for pouring a polygonal column comprises a plurality N of plate members arranged to form a polygonal tube having N sides, where N is an integer greater than or equal to three. The form further comprises a reinforcing framework including a plurality of ring assemblies longitudinally spaced along the tube and interconnected by a plurality of circumferentially spaced longitudinal members. Each ring assembly extends circumferentially about the tube and comprises N ring segments each having an inner surface bearing against an outer surface of a respective one of the plate members, and an outer surface formed as a circular arc. The outer surfaces of the N ring segments collectively form a substantially circular outer surface. The form also includes a plurality of clamps respectively encircling the circular outer surfaces of the ring assemblies and being releasably tightened thereabout.
In one embodiment, the inner surface of each ring segment is substantially planar and includes from one to a plurality of spaced notches therein for respectively accommodating from one to a plurality of the longitudinal members in the notches. The inner surface of each longitudinal member is substantially flush with the inner surface of the ring segment.
In accordance with one embodiment, the first plate member and a first plurality of the ring segments and longitudinal members are secured together forming a first unit, the second plate member and a second plurality of the ring segments and longitudinal members are secured together forming a second unit, the third plate member and a third plurality of the ring segments and longitudinal members are secured together forming a third unit, and the fourth plate member and a fourth plurality of the ring segments and longitudinal members are secured together forming a fourth unit. The first through fourth units are configured to releasably mate with one another at respective side edges of the units such that the tube is formed by the plate members of the units, and such that the ring segments of each unit are aligned with the ring segments of the other units.
The adjacent side edges of the units can releasably mate with one another in any suitable way. In one embodiment, one side edge of each unit defines a rabbet that receives a side edge of an adjacent one of the units so as to form a rabbet joint therebetween.
In one embodiment, each clamp comprises a band clamp that includes a least one metal band and at least one latch. In a particular embodiment, each band clamp includes separate first and second metal bands and first and second latches, the first latch comprising a first latch actuator affixed to one end of the first metal band and a first latch member affixed to one end of the second metal band, the second latch comprising a second latch actuator affixed to the opposite end of the second metal band and a second latch member affixed to the opposite end of the first metal band. The metal bands are configured to extend about one of the ring assemblies and to be secured thereabout by engaging the first latch actuator with the first latch member and the second latch actuator with the second latch member.
Advantageously, the latches comprise over-center latches. Each latch actuator comprises a base having a latch handle connected thereto so as to pivot about a first pivot axis. A latch bail has one end connected to the latch handle so as to pivot relative to the latch handle about a second pivot axis spaced from the first pivot axis, an opposite end of the latch bail being engageable with the latch member. To tighten the metal band and secure the latch, the latch handle is pivoted about the first pivot axis to cause the latch bail to draw the latch member toward the first pivot axis, until the second pivot axis passes to the over-center position.
In accordance with one embodiment, the form comprises four units for forming a square or rectangular column. However, the form can be configured to form columns of three, five, six, or more sides.
Having thus described the disclosure in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
The present invention now will be described more fully hereinafter with reference to the accompanying drawings in which some but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
A concrete form 100 in accordance with one embodiment of the invention is depicted in
As noted, in the illustrated embodiment, the four units 200, 300, 400, 500 are substantially identical. Accordingly, only the unit 200 will be described in detail, with primary reference to
The back side or outer surface 212 of the plate member 210 is reinforced by a reinforcing framework that includes a plurality of ring segments 220 longitudinally spaced along the plate member 210 and secured thereto by any suitable means (including but not limited to adhesive and/or fasteners). The ring segments 220 can be formed of any of various materials, including but not limited to a plastic material, a wood material (e.g., solid wood board or plywood), or other suitable material. Each ring segment 220 has an inner surface 222 that is substantially planar and bears against the outer surface 212 of the plate member 210, and an outer surface 224 formed as a circular arc. In the case of a square concrete form as illustrated, the outer surface 224 extends for approximately 90° of arc; the ring segments of forms for producing columns having a different number of sides would be modified accordingly (e.g., a form for a hexagonal column would have ring segments whose outer surface extends for approximately 60° of arc).
The reinforcing framework for the plate member 210 further comprises at least one longitudinal member 230 that is secured to the outer surface 212 of the plate member (e.g., by adhesive and/or fasteners) and extends along substantially the entire length of the plate member. The longitudinal member(s) can be formed of any suitable material, including but not limited to solid wood board, plywood, plastic, or the like. The inner surface 222 of each of the ring segments 220 has a notch that accommodates each longitudinal member 230, such that the inner surface of the longitudinally member is substantially flush with the inner surfaces of the ring segments. The longitudinal member 230 can be secured in the notch, such as by adhesive and/or fasteners.
In the illustrated embodiment, the reinforcing framework includes three longitudinal members 230, 232, 234 that are circumferentially spaced (i.e., spaced apart along the width of the plate member). The longitudinal member 230 is located at about the midpoint of the width of the plate member, the longitudinal member 232 is located adjacent one longitudinal edge of the plate member, and the longitudinal member 234 is located adjacent the other longitudinal edge of the plate member. As best seen in
The four units 200, 300, 400, 500 are configured such that the ring segments of the units are aligned along the circumferential direction when the units are assembled in the mutually orthogonal configuration such as shown in
As noted, the form 100 further comprises a plurality of band clamps 600. The band clamps respectively encircle the circular outer surfaces of the ring assemblies, i.e., one band clamp per ring assembly, and are releasably tightened thereabout. The structure and function of the band clamps 600 are explained with primary reference to
Each band clamp 600 includes at least one latch 610, i.e., a single latch can be used when a single band is employed as noted above. In the illustrated embodiment having two bands 602, 604, there are two latches 610. Each latch comprises a latch actuator 620 affixed to one end of each metal band and a latch member 630 affixed to the opposite end of each metal band. The metal bands are configured to collectively extend about one of the ring assemblies and to be releasably secured thereabout by engaging the latch actuators 620 with the latch member 630.
In one embodiment, the latches 610 comprise over-center latches as shown. With reference to
While band clamps with latches are illustrated and described in the exemplary embodiment described herein, alternatively the bands can be tightened about the form using other mechanisms such as nuts and bolts engaging brackets secured to the metal bands, or other arrangements.
In operation, the concrete form 100 is used as follows. The form can be transported to the jobsite either in the assembled condition (
The inner surfaces of the units 200, 300, 400, 500 that directly contact the concrete can be covered with a coating or a layer of polymer film (not shown), if desired, in order to facilitate detaching the units from the hardened concrete, and to serve as a water-resistant liner. When a polymer film is used, the film can be glued or stapled to the inner surfaces. The polymer coating or layer can also serve the function of covering any surface roughness or defects (pits, grooves, etc.) in the concrete-contacting surfaces of the units so that the outer surfaces of the concrete column are smooth. Non-limiting examples of release/liner materials that are useful for these purposes include various polymer films, oils, waxes, and the like.
The concrete form 100 can be reused multiple times. The form 100 as described is useful for making square columns, but as noted, the invention is applicable to columns of various numbers of sides. Thus, an N-sided column can be poured using a form comprising a plurality N of units each having a plate member and a plurality of ring segments and one or more longitudinal members generally as described above.
Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.