US3467054A

US3467054A - Concrete wall form installation and tie rod load indicator therefor

Info

Publication number: US3467054A
Application number: US539112A
Authority: US
Inventors: George F Bowden; Richard T Dagiel
Original assignee: Symons Manufacturing Co
Current assignee: General Electric Co
Priority date: 1966-03-31
Filing date: 1966-03-31
Publication date: 1969-09-16
Anticipated expiration: 1986-09-16

Description

Sept. 16, 1969 e. F. BOWDEN ETAL 3,467,054

CONCRETE WALL FORM INSTALLATION AND TIE ROD LOAD INDICATOR THEREFOR Filed March 31. 1966 2 Sheets-Sheet 1 OINVENTORS N GE RGE E aowos F 2 R/CHARD r AG/EL K Sept. 16, 1969 G. F. BOWDEN ET AL 3,467,054 coucma'm WALL FORM INSTALLATION AND TIE non LOAD INDICATOR THEREFOR Filed March 31. 1966 2 Sheets-Sheet 2 82 ,/7s 4 60 I00 I 24 ,A l pf I20 68 52 52 102 I26 I22 DANGER 72 FIG 4 INVENTORS GEORGE E BOWDEN RICHARD 7. DAG/EL United States Patent 3,467,054 CONCRETE WALL FORM INSTALLATION AND TIE ROD LOAD INDICATOR THEREFOR George F. Bowden, Northbrook, and Richard T. Dagiel,

Elk Grove Village, Ill., assignors to Symons Mfg. Company, Des Plaines, Ill., a corporation of Delaware Filed Mar. 31, 1966, Ser. No. 539,112 Int. Cl. G01d 21/00 U.S. Cl. 116--114 3 Claims ABSTRACT OF THE DISCLOSURE A concrete wall form installation embodying a means for ascertaining the pouring of a safe load of wet concrete between the erected panels at the opposite sides of the form structure. A device which indicates the deflection of a certain portion of the studding associated with one of the wall form panels is applied to the studding in the vicinity of a tie rod and the indicated deflection is representative of the tension to which the tie rod is subjected. When this tension approaches the danger point, a visible indication is rendered so that concrete pouring operations may be terminated.

The improved beam deflection apparatus comprising the present invention is desgined for use primarily in connection with measuring the deflection which takes place in the metal studding of a concrete wall form panel when the plywood or other facing of such panel is subjected to bulging under the tremendous thrust of the wet concrete which is poured against the panel during normal intended use of the panel.

In a concrete wall form installation where rectangular wall form panels are arranged or set up in edge-to-edge relation and in opposed relation with a similar series of panels in order to provide two opposed wall form structures wherein the plywood facings of the panels of each structure oppose the plywood facings of the panels of the other structure and wet concrete is poured between the two structures, the horizontally and transversely extending tie rods which connect the two form structures are subjected to extremely high tensional forces which progressively increase in proportion to a certain algebraic power of the height of the mass of the wet concrete between the two structures as it is being poured. If concrete pouring operations are continued indiscriminately, rupture or fracture of the tie rods will take place. Therefore, it is current practice to calculate according to certain mathematical considerations the safe height to which the wet concrete may be poured for a given concrete wall installation, taking into consideration such factors as the number and placement of the tie rods, the distance between the opposed wall form structures, the fluidity of the wet concrete, the known rigidity of the panels, as well as other factors of a varied nature, and to terminate concrete pouring operations when a safe height has been reached in a given region of the installation as a whole. Pouring operations may then be effected along other regions of the installation and during the time required for these latter pouring operations, the initially poured concrete will have time to distribute itself and become settled so that it will sustain the involved load in connection with further pouring operations in this particular region of the installation. A second mass or lift of concrete may then be poured to a calculated safe height and the procedure outlined above repeated. The concrete wall may thus be progressively built up by the pouring of subsequent lifts without the danger of tie rod rupture or fracture. The particular beam deflection apparatus of the present invention makes possible a novel method of "ice concrete pouring in connection with the erection of a concrete wall wherein the deflection of the metal studding of the rectangular concrete wall form panels is correlated with the tie rod load and such deflection is measured so that concrete pouring operations may be terminated at a given location or vicinity of the installation when a predetermined amount of deflection representing the maximum tie rod load has been attained.

The present invention is particularly useful in connection with concrete wall form installations which employ panels of the Steel-Ply type. A Steel-Ply panel consists of a shallow tray-like structure including a rectangular plywood facing, the edges or marginal portions of which are completely encased in a metallic rectangular reinforcing frame comprising transverse and longitudinal frame members, together with a normally vertical series of parallel spaced apart transverse crossbars which extend between the longitudinal frame members and lend reinforcement to the medial or central regions of the plywood facing by constituting a backing therefor. Although the tie rods which extend between the two opposed wall form structures of a concrete wall form installation of the type under consideration are ordinarily connected to such structures at the juncture regions between adjacent panels so that the load on any given tie rod is a function of the tensional forces which are applied to the tie rod between such juncture regions, it is recognized that the localized deflection of the crossbars of the individual panels bears a predetermined relationship to the load which is applied to the tie rods in the vicinity of such crossbars. Therefore, if pouring operations are so conducted that the deflection of a given crossbar is maintained below a predetermined maximum deflection, the load on the tie rods in the vicinity of such crossbar may be kept within safe limits. The novel concrete pouring method of the present invention is predicated upon this principle of beam deflection.

Accordingly, the present invention makes use of a novel beam deflection apparatus which may be quickly attached to or removed from one of the crossbars of a concrete wall form panel and when it is thus applied to the crossbar, it will progressively measure or indicate the deflection of such crossbar while the concrete is being poured against the plywood facing of its panel. A pointer and scale in associated relation with the beam deflection apparatus gives a visual measure of the amount of deflection and certain indicia on the scale is so calibrated as to indicate when a maximum tie rod tension or load has been attained so that concrete pouring operations in the vicinity of the crossbar to which the deflection apparatus is applied may be terminated. The beam deflection apparatus involves, in its general organization, an elongated, horizontally extending reaction bar which carries at its ends a pair of flange clamps for connection to a selected crossbar near the opposite ends of the latter. A medial flange clamp forming part of the apparatus is adapted to be applied to the medial region of the crossbar and it is connected to the reaction bar through a linkage mechanism which has a large magnification factor and by means of which deflection of the selected crossbar is multiplied and also applied to a movable pointer which is associated with a scale on the reaction bar. The scale is suitably calibrated as will be described more in detail hereafter.

The provision of a beam deflection apparatus of the character briefly outlined above makes possible the use of a novel method involving the delayed pouring of wet concrete in connection with the erection of a concrete wall as determined by the indications which are rendered by such beam deflection apparatus. The provision of a concrete wall form installation embodying the use of such a tie rod load indicator constitutes the principal object of the present invention.

Other objects and advantages of the invention, not at this time enumerated, will become readily apparent as the nature of the invention is better understood.

In the accompanying two sheets of drawings forming a part of this specification, one illustrative embodiment of a beam deflection apparatus utilizing the principles of the present invention is shown, together with a disclosure of the manner in which it is employed in connection with a concrete pouring operation.

In these drawings:

FIG. 1 is a fragmentary perspective view of a portion of a standard or conventional concrete wall form installation embodying two opposed spaced apart series of Steel- Ply panels, the panels of each series being arranged in edge-to-edge relation, the opposed side structures of the installation being maintained in their spaced relationship by horizontal transversely extending tie rods, and certain of the crossbars of one of the panels being provided with two beam deflection apparatuses embodying the present invention;

FIG. 2 is a plan view of one beam deflection apparatus;

FIG. 3 is an enlarged perspective view of the beam deflection apparatus of FIG. 2, showing the same operatively applied to a panel crossbar;

FIG. 4 is a further enlarged fragmentary plan view of a portion of the beam deflection apparatus of FIG. 2, showing such apparatus applied to a crossbar before concrete pouring operations have commenced and when the crossbar is in a state of equilibrium;

FIG. 5 is a fragmentary plan view similar to FIG. 4, but showing the crossbar to which the apparatus is applied under deflection and beyond the safe limit of concrete pouring operations; and

FIG. 6 is a perspective view on a reduced scale, showing the reaction bar of the improved beam deflection apparatus before being attached to a panel crossbar.

Referring now to the drawings in detail and in particular to FIG. 1, a conventional concrete wall form installation is designated in its entirety by the reference numeral 10 and involves in its general organization two series 12 and 14 of rectangular concrete wall form panels 16, the panels of each series being arranged in upstanding and edge-to-edge relationship. The panels 16 of the two series are maintained in spaced parallel relationship by means of horizontal, transversely extending tie rods 18, two such tie rods being illustrated in FIG. 1 as being associated with two adjacent panels of each series in the production of a concrete wall which is to be formed by pouring of wet concrete between the two series 12 and 14.

The illustrated panel units 16 are of the prefabricated Steel-Ply type, which is to say, that they consist of rectangular plywood facings 20 and rectangular steel studding or reinforcing frames around the edge or marginal portions of the facings 20, said frames being disposed for the most part outwards of the outer faces of the panels and consisting of vertical frame members 22 and horizontal frame members 23. At appropriate levels in the concrete form installation, suitable crossbars 24 of angle shape design extend across the outer faces of the panel facings 20 and between the vertical frame members 22.

Specifically, the vertical frame members 22 are in the form of structural steel bars which are generally of shallow U-shaped cross section and include spaced marginal

parallel ribs

26 and 28 and connecting bases or web portions 30. On the side of each web portion 30 that is opposite the

ribs

26 and 28 is a shallow longitudinally extending rib 32 and it defines an angular groove or recess 33 for reception therein of the adjacent vertical edge region of the associated plywood facing 20. The horizontal crossbars 24 have the ends thereof welded to the inside faces of the web portions 30 of the vertical frame members 22. At vertically spaced regions along the vertical frame members 22, the

ribs

26 and 28 are notched as at 34 to accommodate the end portions of the tie rods 18, while the web portions 30 of the vertical frame members 22 are formed with rectangular slots 36. The latter are in horizontal register with the notches 34 and are adapted for reception therethrough of the bolts of conventional connecting bolt and wedge assemblies 38 by means of which adjacent wall form panels 16 are fastened together, all in a manner that is well known in the art.

The tie rods 18 are each in the form of a length of flat sheet metal stock of rectangular cross section and of a longitudinal extent appreciably greater than the over-all width of the spaced series 12 and 14 of wall form panels 16. Spaced apart slots 44 are formed in the end portions of the tie rods 18 for selective register with the slots 36 in the web portions 30 of the vertical frame members 22 when the concrete wall form installation 10 is assembled to the end that the bolts of the bolt and wedge assemblies 38 may cooperate with the slots 36 and 44 in securing the end portions of the tie rods 18 in position between adjacent panels 16.

It has previously been set forth in the preamble or introductor part of this specification that, when wet concrete is poured between the two series 12 and 14 of the connected panels 16, the tie rods 18 are placed under tension and that the pouring of each lift or layer of concrete must be terminated in a given region of the form installation before the maximum safe load on the tie rods in the vicinity of pouring operations is exceeded. When wet concrete is poured between the two series 12 and 14 of panels, not only does outward bulging take place due to the lateral forces which are applied to the form installation at the juncture regions between adjacent panels, but bulging of the plywood facings of the individual panels takes place and is restrained by the existence of the crossbars 24, and as a consequence, these crossbars are subject to lateral outward deflection. Therefore, the amount of lateral deflection which takes place in any given crossbar 24 is a fairly accurate measure of the tension which has been attained in the adjacent group of tie rods 18, this tension depending, of course, upon the number of tie rods employed, the greater the number of tie rods, the greater the load which these tie rods, considered collectively, will withstand. In order to measure the deflection of a given crossbar 24, there has been provided, according to the present invention, a novel beam deflection apparatus 50 which is capable of being quickly and easily applied to and removed from a selected crossbar 24.

Referring now, additionally, to FIGS. 2 to 6, inclusive, the beam deflection apparatus 50 of the present invention involves in its general organization a horizontal reaction bar 52 which is of outwardly bowed configuration and has a short central portion 54 with

elongated end portions

56 and 58. The latter extend at obtuse angles to the central portion 54 of the reaction bar. Said central portion 54 is formed with ahorizontally inwardly extending shelf or anchor ledge 60, while the extreme outer or distal ends 62 of the

end portions

56 and 58 are turned outwardly away from each other so that they extend in coaxial or coplanar relationship. Said distal ends 62 have secured thereto by rivets or other suitable means flange clamps 64 which are in the form of conventional C-clamps and have clamping screws 66 associated therewith. The flange clamps 64 are thus maintained in spaced relationship at a fixed distance from each other and they are adapted to be fixedly secured to the end regions of a selected crossbar 24. An inwardly extending anchor ledge 68 is formed on the end portion 58 of the reaction bar 52 and pivotally supports thereon an indicating pointer arm 70. The latter is associated with a scale plate 72 which is fastened by screws 74 to an outwardly extending anchor ledge 76 on said end portion 58 of the reaction bar 52. A medial screw-equipped flange clamp 80 is adapted to be secured to the central portion of the associated crossbar 24 and is operatively connected through the medium of a threeelement linkage mechanism including a first thrust link 82, a lever 84, and a second thrust link 86 to the pointer arm 70 for magnification of the defleceion of the crossbar 24 in a manner that will be described presently. The three elements of the previously mentioned linkage mechanism are each in the form of short lengths of flat bar stock, the thrust link 82 having the inner end thereof pivotally connected to a stud-forming nut and bolt assembly 88. The latter is fixedly mounted on and extends through an outwardly projecting flange 90 on the medial flange clamp 80. The outer end of the thrust link 82 is pivotally connected by a stud-forming nut and bolt assembly 94 on the inwardly extending anchor ledge 60. The lever 84 is a first class lever which has a large magnification factor and consists of a short lever arm 98 which extends between the stud-forming

assemblies

92 and 94, and a long lever arm 100 the distal end of which is pivotally connected by means of a nut and bolt assembly 102 to one end of the thrust link 86. The other end of the thrust link 86 is pivotally connected to a studforming nut and bolt assembly 104 on the pointer arm 70. As shown in FIG. 3, the pointer arm 70 is pivotally connected medially of its ends on a stud-forming nut and bolt assembly 106 on the inwardly extending anchor ledge 68. Said pointer arm 70 also has a large magnification factor and includes a pointer proper 110 which overlies the scale plate 72.

When the beam deflection apparatus 50 of the present invention is to be employed for measuring the deflection of a beam, the scale plate 72 may be calibrated by the application thereto of indicia which is representative of any desired condition, as, for example, the amount of deflection of the beam measured in suitable units such as fractions of an inch, a centimeter, or the like. For the specific use for which the apparatus has been designed in connection with the deflection of a panel crossbar such as one of the crossbars 24, it is desirable that the scale plate 72 be calibrated to indicate a safe load that may be applied to selected groups of tie rods 18 in the vicinity of the crossbar to which the apparatus 50 is applied. Therefore, as clearly shown in FIGS. 4 and 5, this scale plate 72 is provided with a first radial indicia line 120 which is representative of the maximum safe load which may be tolerated for a given installation when the adjacent tie rods are spaced apart on relatively close tie rod anchoring centers, for example, two-foot centers. The scale plate is provided with a second radial indicia line 122 which is indicative of the safe load which may be applied to the adjacent tie rods when these tie rods are spaced apart a lesser distance, for example, on one-foot centers. The two

indicia lines

120 and 122 may be associated in a pattern on the scale plate 72 wherein a green area 124 on the face of the scale plate represents safe loading of the ties rods, while a red area 126 represents danger loading. Obviously, the scale plate 72 may be calibrated to suite the expediences of any given loading condition of the beam to which the apparatus 50 may be applied.

Referring again to FIG. 1 wherein a typical concrete wall form installation is fragmentarily shown, the use of one or more of beam deflection apparatuses 50 makes possible a novel method of safely pouring concrete between the two side structures of a given wall form installation. It is contemplated that either one of the apparatuses 50 will be applied successively to a lower crossbar of a selected panel 16 and then to a higher crossbar or that a plurality of beam deflector apparatuses will be applied, as shown in FIG. 1, to alternate crossbar 24 of a selected panel 16, the particular selected panel preferably being one which is disposed in the vicinity of the form where concrete pouring operations are initially undertaken.

Assuming the concrete wall form insulation that is' fragmentarily shown in FIG. 1 to be of great length, pouring operations may be commenced in the vicinity of the right-hand panel 16. The concrete is poured between the two series 12 and 14 of the installation 10 in the vicinity of said right-hand panel and the wet concrete falls on the installation foundation between the two series 12 and 14 and commences to build up between the two side structures of the form. The lowermost crossbar 24 to which one of the beam deflection apparatuses 50 is applied will become deflected accordingly. Where the tie rods are attached to the panels 16 on two-foot centers as shown in FIG. 1, outward deflection of the lowermost crossbar of the right-hand panel occurs as the concrete is poured and causes the pointer to move outwardly over the scale plate 72. As soon as the pointer registers with the radial indicia line 120, the concrete pouring operations will be terminated in the particular region involved, but may be progressively carried on in other regions of the installation. In a short period of time, usually the time that is consumed by these remote pouring operations, the initially poured concrete will have settled to such an extent that the settled concrete is then ready to bear an additional load or lift of concrete above the same. When this occurs, pouring operations may again be conducted in the vicinity of the first pouring operation and such additional concrete as may be piled upon the originally poured concrete Will have no effect upon the three-element linkage mechanism that is associated with the lowermost beam deflection apparatus 50 since the concrete in the vicinity of this apparatus has become settled as well as hard. During the second pouring operation in this particular region of the installation 10, the next higher beam deflection apparatus 50 above the first apparatus will then be watched for crossbar deflection and pouring operations again terminated when this second apparatus renders an indication which is represented by register of the pointer 110 with the radial indicia line The second lift of concrete will then be poured in a similar manne by transferring the pouring operations to other regions of the installation 10, returning to the original pouring region only when the second lift of concrete has become settled and hardened. Such pouring operations are repetitious, there being one beam deflection apparatus to indicate safe pouring of each lift.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the invention. Therefore, only insofar 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. In a concrete wall form installation, the combination with a vertically disposed wall form panel at one side of the form installation and having a rectangular plywood facing surrounded by a metallic reinforcing frame including vertically disposed side frame members, horizontally disposed top and bottom frame members, and a transversely extending horizontally and medially disposed crossbar extending between said side frame members and secured thereto at its ends for reinforcing said plywood facing against outward bulging under the influence of the force of wet concrete poured against the inside face of said facing, said frame members and crossbar constituting the panel studding, a tie rod having one end connected to one of said vertically disposed side frame members in the immediate vicinity of the adjacent end of the crossbar, projecting across the form installation, and having its other end secured to a reaction point on the opposite side of said form installation, of a tie rod load indicator for measuring the deflection of said crossbar and thereby closely indicating the amount of tension that is incurred in the tie rod, said tie rod load indicator comprising a horizontally disposed elongated reaction bar, a clamping device at each end of said reaction bar releasably and fixedly secured to the studding adjacent to the ends of said crossbar respectively, the medial region of said reaction bar being offset outwardly away from said crossbar, a dial and pointer type indicator mounted on said offset medial region of the reaction bar, and means operatively connected to said indicator and engageable with the central region of said crossbar for actuating said indicator.

2. In a concrete wall form installation, the combination set forth in claim 1 and wherein said clamping devices are releasably secured directly to the crossbar adjacent the opposite ends thereof respectively.

3. In a concrete wall form installation, the combination set forth in claim 2 and wherein said dial and pointer type indicater includes a planar dial and a pointer adapted to traverse the dial, said dial having two indicia areas thereon designed for cooperation with the pointed, one of said indicia areas being indicative of accumulated degrees of tension in said tie rod which are safely below the rupture tension of the rod, and the other area being indicative of accumulated degrees of tension in the rod which render the rod subject to rupture.

References Cited UNITED STATES PATENTS 3/1912 De Lotbiniere 11634 1,306,891 6/1919 Grafton 73-144 2,029,111 1/1936 Lester 73144 2,285,471 6/1942 Sturgess 116129 XR 2,743,607 5/1956 Decker 73-444 3,174,334 3/1965 McKerrnah 73144 LOUIS J. CAPOZI, Primary Examiner US. Cl. X.R. 73-144