US3661354A

US3661354A - Reinforced concrete wall form panel

Info

Publication number: US3661354A
Application number: US54501A
Authority: US
Inventors: Richart T Dagiel; David L Cody
Original assignee: Symons Corp
Current assignee: General Electric Co
Priority date: 1970-07-13
Filing date: 1970-07-13
Publication date: 1972-05-09
Anticipated expiration: 1989-05-09
Also published as: DE2128609A1; FR2094998A5; GB1343051A

Abstract

A reinforced concrete wall form panel of the ''''Steel-Ply'''' type and consisting of a steel-studded rectangular plywood facing which is reinforced by horizontally disposed, vertically, spaced, transverse crossbars which define included openings therebetween. Additional vertically disposed, horizontally spaced, longitudinal backbone members extend the full length of the panel, intersect the transverse crossbars, extend across the included openings and provide a plate action which limits the deflection of the plywood facing to substantially the deflection of such crossbars, while at the same time preventing rotation of the crossbars.

Description

United States'Patent Dagielet a1.

[451 May 9, 1972 ,[73] Assignee:

[54] REINFORCED CONCRETE WALL FORM PANEL [72] Inventors: Richart T. Dagiel, Elk Grove Village; David L. Cody, Hoffman Estates, both of 111.

Symons Corporation, Des Plaines, 111. [22] Filed: July 13, 1970 [21} App1.No.: 54,501

[52] 11.5. C1 [51] Int. Cl ..E04g ll/06 [58] Field ofSearch .2249/189, 191, 192, 193, 194, 249/219 W, 219 R, 44, 49, 23, 190, 196, 18, 33, 40,

45; 25/131 P, 131 R, 131 T [56] References Cited UNITED STATES PATENTS 2,017,553 1Q/1935 Troiel ..249/45 X 2 801,454 8/1957 Troiel ....249/l90 3,362,674 1/1968 Gilbertm. ..249/49 1,694,292 12/1928 Tracey... ..25/131 P 2,336,253 12/1943 Jennings ..249/196 X 2,451,951 10/1948 Howat ..249/33 2,51 1,584 6/1950 Hill ..249/44 X 2,595,286 5/ 1952 Otte ..249/49 2,616,148 l1/1952 Hawes ..25/l31 P X 3,007,221 11/1961 Kenney.... ..25/13l T 3,211,413 10/l965 Low ..249/l90 X Primary Examiner-J. Spencer Overholser Assistant Examiner-John S. Brown Attorney-Norman H. Gerlach [5 7 ABSTRACT A reinforced concrete wall form panel of the Steel-Ply" type and consisting of a steel-studded rectangular plywood facing which is reinforced by horizontally disposed, vertically, spaced, transverse crossbars which define included openings therebetween. Additional vertically disposed, horizontally spaced, longitudinal backbone members extend the full length of the panel, intersect the transverse crossbars, extend across the included openings and provide a plate action which limits the deflection of the plywood facing to substantially the deflection of such crossbars, while at the same time preventing rotation of the crossbars. v

6 Claims, 6 Drawing Figures REINFORCED CONCRETE WALL FORM PANEL The present invention relates to a novel panel for use with similar panels in connection with the erection of a concrete wall form, the panel being of the Steel-Ply" type and having novel reinforcing means for the plywood facing thereof, such means affording a more effective bracing of the plywood facing against outward bulging than has heretofore been possible while, at the same time, prescribed weight limitations are not exceeded.

The invention is specifically concerned and also designed for use primarily with prefabricated Steel-Ply" panels of the type which is manufactured and sold by Symons Corporation of Des Plaines, lllinois. Such a concrete wall form panel is shown and described in U.S. Pat. No. 2,997,769, granted on Aug. 29, 1961 and entitled TIE ROD ASSEMBLY FOR CONCRETE WALL FORM PANELS. invariably, such a panel consists essentially of a shallow tray-like structure in the form of a flat rectangular plywood facing, the margins or edges of which are completely encased in a rectangular steel reinforcing frame including vertical and horizontal frame members, as well as vertically spaced, horizontally extending crossbars between the vertical frame members. Such a panel, when used in a concrete wall form installation, is adapted to be arranged in edge-to-edge relationship with similar panels and in such a manner that all of the plywood facings lie in a common horizontal plane in order that wet concrete may be poured against the continuous unbroken wall-supporting surface that is offered by the plywood facings of the panels, it being understood that the series of panels will form one side of the concrete wall form as a whole and that the form will have another similar upstanding side which is positioned in spaced apart relation with the first side, the two sides of the form being maintained in their spaced apart relationship by way of horizontal tie rods which extend transversely across the space between the sides and are connected to such sides by way of T-bolt and wedge assemblies at their ends.

In order to accommodate the concrete hardware which is used with concrete wall form panels of the type under consideration, the vertical and horizontal members of the reinforcing frames have formed therein transverse slots, such slots being set at approximately l-foot centers. Most of the hardware that is employed is designed to cooperate with these slots and included in such hardware are the aforementioned T-bolt and wedge assemblies which are employed for the purpose of drawing the adjacent side edges of the panels together and attaching the panels to the ends of the tie rods.

in the large size concrete wall form panels which constitute as much as 95 percent of all the panels which are manufactured and used, it is absolutely essential that the medial regions of the plywood facings be reinforced against outward bulging under the tremendous outward thrust of the poured wet concrete and, accordingly, the aforementioned crossbars are provided and they divide the rectangular reinforcing frames into a number of included frame openings which are rectangular and have their long dimension extending transversely or crosswise of the panels. In order to maintain a spacing as nearly as possible to 12 inches, the crossbars of each concrete wall form panel are caused to traverse the reinforcing frame slightly above or slightly below the level of the slots in the vertical frame members. To preserve end-for-end reversibility of each panel, all of the crossbars on one side of a medial horizontal plane are positioned just above the level of the adjacent slots in the vertical frame members, while the crossbars on the other side of such plane are positioned just below the level of the adjacent slots in said vertical frame members. This obviously establishes a medial or central included opening which is of greater height than the other openings. The crossbars of a Steel-Ply concrete wall form panel are ordinarily in the form of angle pieces which are of L- shaped cross section and, when installed, one flange of each crossbar extends vertically and lies flatlyagainst the outer surface of the plywood facing. This direction of extent of the various vertically disposed crossbar flanges still further modifies the height of the included openings between the various crossbars of the rectangular reinforcing frame of the panel. When the vertically disposed flanges of the crossbars extend in the same direction, the height of the included opening between adjacent crossbars is reduced. When such flanges extend away from one another in opposite directions, the height of the included opening is increased.

Considering only the arrangement of the horizontal crossbars of the present Steel-Ply" panel, such crossbars are designed so that equal crossbar spacing may be attained, thus rendering the various included openings between adjacent crossbars substantially the same in size or area and without sacrificing reversibility of the panel. To accomplish this, the crossbars of the reinforcing frame of the concrete wall form panel are formed of a balanced Z-shaped steel stock instead of L-shaped orangle piece steel stock, the Z-shaped stock being more efiicient structurally. All of the crossbars are similarly oriented with the flanges which lie against the outer surface of the plywood facing projecting upwardly from the medial webs of the crossbars. By reason of this, an incidental advantage accrues in that the flanges of the crossbars which are remote from the plywood extend downwardly and thus shed any loose concrete which might accumulate on the webs of the crossbars during erection of handling of the improved panel.

Further than this, in connection with a conventional Steel- Ply panel, the plywood facing which is employed is invariably in the form of a laminated structure of the five-ply variety with the thickness of the laminations being equal and with the overall thickness of the facing being-one-half inch so that the individual plies are each one-tenth of an inch thick. As purchased from the manufacturer for subsequent fitting operations in connection with the installation of the plywood facing in the rectangular steel reinforcing frame, the grain structures of the various plies of the facing run at right angles alternately in different directions so that the outside or surface plies as well as the center ply, have their grain running in the same direction. Based solely upon numerical superiority, it is obvious that a plywood facing of this character will have greater-strength against flexing in one direction than it will in the other. As a matter of fact, when the plywood facing is subjected to bending or flexing stresses across a given span, only those plies which have their grain running lengthwise of the span are considered as carrying the load. The cross plies, being stressed across the grain, are incapable of contributing any significant amount of resistance to such bending or flexing.- These considerations are not altered appreciably by the fact that the plywood facing of a concrete wall form panel is supported along all four margins or edges since the reinforcement offered at the margins or edges is effective only in the immediate vicinity of the frame members. For these reasons, and in order to attain greatest resistance .to outward bulging or flexing, it is customary to cut and install the plywood facing in the rectangular frame of a conventional Steel-Ply" panel so that the predominance of grain structure in the plywood plies runs in the direction of the shortest span of each included opening in the rectangular reinforcing frame of the panel. This fact should be borne in mind in connection with the following considerations which are given to the deflection of the plywood facing across each included opening in the frame of a standard Steel-Ply panel, the deflection arising, of course, under the pressure of wet concrete and the deflection resulting in a pillow block" or quilting effect which is left in the finished concrete wall after removal of the panel.

Theoretical considerations have shown that the maximum deflection of a beam under load across a given span, i.e., the deflection at mid-span, may be represented by the equation A K WLIEI where A represents maximum deflection, K is a constant that varies with the type of span, W is the weight per unit of length, L is the length of the span, E is the modulus of elasticity of the beam, and I is the moment of inertia. From I this equation, it will be seen that maximum deflection varies as a function of the fourth power of the length of the span and, consequently, any reduction in the length of the span, however small, will effect a material reduction in the amount of beam deflection.

From the above considerations of plywood grain direction, it is obvious that by the use the aforementioned Z-shaped crossbars and the equal spacing thereof, the various included openings between adjacent crossbars are, according to the present invention, equalized in size so as to eliminate the large central included opening where plywood bulging is at a maximum. In addition to this, the present invention contemplates the provision of a series of vertically extending, equidistantly spaced backbone members which span the panel completely from the lower horizontal frame member to the upper horizontal frame member, intersect the various crossbars and bear against the outer surface of the plywood facing, thereby dividing each included opening between adjacent crossbars into smaller included openings of relatively equal size. These vertical backbone members take advantage of the cross grain construction of the plywood facing and reduce the outward bulging or flexing that ordinarily would take place in each included opening between adjacent crossbars to substantially whatever small deflection is present in the crossbars themselves. Since these vertical backbone members extend in the same direction as the predominant grain of the plywood facing and since the factor L" in the above equation is reduced, a tremendous reduction in localized plywood facing bulging within the confines of any given panel results and the aforementioned objectionable quilting effect in the side surface of the finished concrete wall is of such negligible proportions that it is unnoticeable. The net results of this is to provide an extremely rigid framework of lattice-like design which entails less increase in weight over conventional Steel-Ply" panels than do many of the special previously designed Steel-Ply panels for the same purpose, namely, to inhibit plywood facing bulging and which, in any event, affords a concrete wall form panel which is acceptable in weight so that it may readily be handled by a workman in erecting a given form.

The provision of a Steel-Ply panel of the character outlined above, and possessing the stated advantages, constitutes the principal object of the present invention.

A further advantage of the invention resides in the fact that the general operating characteristics of a conventional Steel- Ply panel are, in their entirely preserved and a concrete wall form panel embodying the principles of the present invention does not differ appreciably from a standard Steel-Ply" panel insofar as erection accommodations are concerned, such as the use of conventional flat slotted tie rods, T-bolt and wedge fastening devices and the like, or the use of conventional concrete wall form hardware such as waler clamping brackets, form braces and other panel adjuncts. As a matter offact, a Steel-Ply" panel embodying the present invention may be used interchangeably with a conventional Steel-Ply panel in any given installation.

Other advantages and objects of the invention, not at this time enumerated, will readily suggest themselves as the nature of the invention is better understood from a consideration of the following detailed description.

The invention consists in the several novel features which are herewith set forth and are more particularly defined by the claims at the conclusion hereof.

In the accompanying two sheets of drawings forming a part of this specification, one illustrative embodiment of the invention is shown.

IN THESE DRAWINGS:

FIG. 1 is a fragmentary perspective view of a concrete wall form utilizing panels embodying the present invention;

FIG. 2 is an enlarged fragmentary perspective view of the juncture region between a crossbar and backbone angle piece employed in connection with the invention;

FIG. 3 is an enlarged fragmentary perspective view of one side of an assembled concrete wall form embodying three of the panels, the latter being shown operatively connected together in edge-to-edge relationship;

FIG. 4 is a vertical sectional view taken on the line 44 of FIG. 3;

FIG. 5 is a vertical sectional view taken on the line 5-5 of FIG. 4; and

FIG. 6 is a horizontal sectional view taken on the line 6-6 of FIG. 1.

Referring now to the drawings in detail and in particular to FIG. 1 wherein an erected concrete wall form employing the improved panels is fragmentarily shown, the front and rear sides of the form are designated by the

reference numerals

10 and 12, respectively, and each side is comprised of a number of panels 14 embodying the principles of the present invention and arranged in edge-to-edge relationship. The two

form sides

10 and 12 are maintained in their upstanding and spaced apart relationship by means of conventional horizontally and transversely extending tie rods 16 which are fastened or connected to the panels 14 by T-bolt and wedge assemblies 18 in a manner that will be described presently.

Each panel 14 is of the prefabricated Steel-Ply" type, which is to say that it is of open shallow tray-like design and consists of a rectangular plywood facing 20 and a marginal rectangular steel reinforcing frame, such frame comprising longitudinal frame members 22 and transverse frame members 23. The panels 14 are shown in FIG. 1 as being positioned with their longitudinal frame members 22 extending vertically and with their transverse frame members 23 extending horizontally and thus further reference to these panels will be made on the basis of their position in the wall form. At appropriate levels in the panels 10 intermediate horizontal steel crossbars 24 in the fonn of structural steel bars of Z-shape cross section extend between and are welded to the opposed vertical frame members 22. The plywood facing 20 consists of five face-to-face bonded-together plies. For the purpose of obtaining maximum strength, the central and the two outside plies have the grain extending lengthwise while the two plies between the central and outside plies have the grain extending transversely.

The vertical and

horizontal frame members

22 and 23 are in the form of structural steel bars which are shallow channelshaped in cross section and each bar consists of inside and outside outwardly extending

marginal ribs

26 and 28 and a connecting base or web portion 30. On the side of each web portion opposite to the

ribs

26 and 28 is a lateral inwardly extending flange 32 (see FIG. 3) on which the adjacent marginal portion of the plywood facing 20 seats with its inside face flush with the inside edge portions of the

frame members

22 and 23. At vertically spaced regions along the

marginal ribs

26 and 28, pairs of transversely registering notches 34 are formed and these notches, when the vertical frame members 22 are in contiguity, define therebetween horizontal channel voids 35 which are adapted to receive therethrough the slotted ends of the tie rods 18. A rectangular slot 36 is formed in the web portion 30 of each frame member at the level of each pair of notches 34 and such slot is adapted to receive therethrough the shank portion of the T-bolt of one of the assemblies 18 whereby the contiguous or abutting frame members of adjoining panels are drawn tightly together. The various groups of notches 34 and slots 36 are formed on 12-inch centers and in such a manner as to insure that when end-over-end reversibility of any panel is resorted to, notch alignment between contiguous frame members will be preserved. The aforementioned tie rods extend through the aforementioned channel voids 35 and the slotted ends thereof register with the adjacent slots 36 so that the shank portions of the T-bolts of the T-bolt and wedge assemblies 18 pass through such slotted ends and thus capture the tie rods in a manner well known in the art.

As is customary in connection with most Steel-Ply" panels, short diagonal strut pieces 38 extend across the four corners of each panel 14 on the outer side thereof, are welded at their ends to the vertical and

horizontal frame members

22 and 23, and are riveted to the plywood facing 20.

The arrangement of the concrete wall form panel thus far described, with the exception of the specific cross-sectional shape of the crossbars 24 and their inside flange placement, is

purely conventional, which is to say that it conforms to the specifications of a conventional Steel-Ply" panel. According to the present invention, the crossbars 24, instead of being of L-shape construction as heretofore manufactured, are of Z- shape in design and each crossbar includes medial web 40, an inside upwardly projecting inside flange 42 which lies flush against the plywood facing 20, and a downturned outside flange 44. The ends of the web portions 40 of the crossbars 24 are slotted as indicated at 46 to afford a clearance for the wedges of the T-bolt and wedge assemblies 18 when the wedges are driven downwardly through the slotted distal ends of the T-bolts as is customary in connection with conventional Steel-Plypanels.

The principal modification of a standard Steel-Ply panel, according to the present invention, resides in the provision of a pair of vertically extending backbone members 50 which are in the form of L-shaped angle pieces. Each backbone member embodies an inside flange 52 which fits flatly against the outer surface of the plywood facing 20, and an outwardly directed flange 54 which extends at right angles to the plywood facing. As best illustrated in FIG. 3, the inside flanges 52 of the two backbone members 50 extend in opposite directions, i.e., away from one another. The backbone members 50 extend continuously between the top and bottom horizontal frame members 23 of the reinforcing frame and are welded to the latter at their ends. The lateral disposition of the spaced apart backbone members 50 is such that they, in combination with the various crossbars 24 which they intersect, establish a lattice-like framework having (in the illustrated large size Steel- Ply panels) 18 included nearly square openings of substantially equal size. It will be understood, of course, that where smaller size Steel-Ply" panels oflesser height are concerned, and having a lesser number of crossbars, the number of included openings will be correspondingly less, there being three less openings for each crossbar which is eliminated or omitted.

The manner in which the backbone members 50 intersect the crossbars 24 is clearly shown in FIG. 2 wherein it will be observed that, at each intersection, the web portion 40 of the crossbar is formed with a narrow notch 56 (see FIG. 2) that receives the outwardly directed flange 54 of the backbone member 50, while the flange portion 42 of the crossbar is formed with a wide notch 58 that receives the inside flange 52 of the backbone member. The flange 42 of the crossbar 24 and the flange 52 of the backbone member 50 are coplanar and both bear flatly against the outer surface of the plywood panel 20. In the manufacture or assembly of a given concrete wall form panel 10, after a particular backbone member 50 has been received in the

notches

56 and 58 in the associated crossbar 24, the juncture regions of the two parts or members are welded together as indicated at 60.

Various assembly procedures are available for producing the panels 14 of the present invention. If desired, the entire plywood panel-reinforcing structure which lies within the confines of the rectangular reinforcing frame embodying the

members

22 and 23 may be assembled as a unitary lattice unit and then inserted into the frame and welded in position therein with the various welds being made at the regions where the extreme ends of the crossbars 24 and the backbone members 50 abut against the vertical frame members 22 and the horizontal frame members respectively. Alternatively, if desired, the backbone members 50 may be installed in the reinforcing frame at the proper locations and, thereafter, the crossbars 24 may be interlocked with the backbone members 50 as previously described in connection with FIG. 2, and then welded in position. Irrespective, however, of the particular method of assembling the panels 10, the essential features of the invention remain the same.

From the above description, and particularly from the theoretical considerations set forth in the introductory or preamble portion of this specification, it is believed that the manner in which the use of Z-shaped crossbars 24 with vertically extending and intersecting angle-type backbone members 50 provides an effective reinforcing arrangement for preventing outward bulging of the plywood panel facing 20 so that no quilting" or pillow block effect will remain in the finished concrete wall after the concrete form panels have been removed therefrom. However, at the risk of repetition as is stated that by reason of these vertical backbone members 50 the deflection of the plywood facing 20 is limited substantially to the deflection which takes place in the crossbars 24 themselves.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in thisspecification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the invention. For example, although each panel 14 is shown and described herein as being provided with two spaced apart vertical backbone members 50. a greater or lesser number of such members may be employed if desired, the only consideration being the maintenance of the overall panel within acceptable weight limitations. Therefore, only in sofar as the invention is particularly pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

1. A concrete wall form panel adapted to be positioned vertically in edge-to-edge relation with like panels in order to form a part of a concrete wall form, said panel comprising a rectangular plywood facing and a rectangular marginal reinforcing frame including verticalframe members and top and bottom horizontal frame members, saidvertical frame members being provided with vertically spaced pairs of opposed bolt-receiving openings at equally spaced levels, a series of transversely extending horizontal plywood-reinforcing crossbars having their ends secured to the vertical frame members, there being one crossbar for each pair of opposed openings, each crossbar being Z-shape in transverse cross section and having a horizontal shelf-like web which is vertically displaced from the horizontal plane of the associated pair of openings a slight distance, a first flat vertical inside flange which bears coextensively against the plywood facing, and a second flat vertical outside flange which projects in a direction opposite to the direction of projection of the first inside flange of the crossbar, all of said crossbars extending in parallelism and defining in combination with said vertical frame members a series of rectangular included openings between adjacent crossbars, and at least one vertically extending backbone member spanning the distance between said top and bottom horizontal frame members and intersecting the crossbars, said backbone member having a flat inside flange which bears coextensively against the plywood facing, and an outwardly directed flange which extends at a right angle to the last mentioned inside flange.

2. A concrete wall formpanel as set forth in claim 1 and wherein said flat vertical inside flange of each crossbar projects upwardly, and the third flat vertical outside flange projects downwardly.

3. A concrete wall form panel as set forth in claim 2 and wherein the horizontal shelf-like web of each crossbar is formed with a narrow notch through which the flat vertical outside flange of the backbone member projects, and the vertical inside flange of each crossbar is formed with a wide notch through which the flat inside flange of the backbone member projects, said inside flanges being coplanar.

4. A concrete wall form panel as set forth in claim 3 and wherein there are two backbone members and they divide each of the included openings between adjacent crossbars into three substantially equal width openings.

5. A concrete wall form panel as set forth in claim 4 and wherein the crossbars and backbone members are welded together at their regions of intersection and thus provide a rigid lattice-like reinforcement for the plywood facing within the rectangular confines of the marginal reinforcing frame and in which the various lattice-openings are substantially equal in size.

placed slightly above the horizontal plane of its associated pair of openings in the vertical frame members.

8. A concrete wall fonn panel as set forth in claim 7 and wherein the plywood facing is comprised of five plies and has a predominant grain direction which extends vertically.

I I l

Claims

1. A concrete wall form panel adapted to be positioned vertically in edge-to-edge relation with like panels in order to form a part of a concrete wall form, said panel comprising a rectangular plywood facing and a rectangular marginal reinforcing frame including vertical frame members and top and bottom horizontal frame members, said vertical frame members being provided with vertically spaced pairs of opposed bolt-receiving openings at equally spaced levels, a series of transversely extending horizontal plywood-reinforcing crossbars having their ends secured to the vertical frame members, there being one crossbar for each pair of opposed openings, each crossbar being Z-shape in transverse cross section and having a horizontal shelf-like web which is vertically displaced from the horizontal plane of the associated pair of openings a slight distance, a first flat vertical inside flange which bears coextensively against the plywood facing, and a second flat vertical outside flange which projects in a direction opposite to the direction of projection of the first inside flange of the crossbar, all of said crossbars extending in parallelism and defining in combination with said vertical frame members a series of rectangular included openings between adjacent crossbars, and at least one vertically extending backbone member spanning the distance between said top and bottom horizontal frame members and intersecting the crossbars, said backbone member having a flat inside flange which bears coextensively against the plywood facing, and an outwardly directed flange which extends at a right angle to the last mentioned inside flange.

2. A concrete wall form panel as set forth in claim 1 and wherein said flat vertical inside flange of each crossbar projects upwardly, and the third flat vertical outside flange projects downwardly.

6. A concrete wall form panel as set forth in claim 5 and wherein the flat inside flanges of the two backbone members project laterally from their associated outwardly directed flanges in the same direction.

7. A concrete wall form panel as set forth in claim 6 and wherein the horizontal shelf-like web of each crossbar is displaced slightly above the horizontal plane of its associated pair of openings in the vertical frame members.

8. A concrete wall form panel as set forth in claim 7 and wherein the plywood facing is comprised of fivE plies and has a predominant grain direction which extends vertically.