AU2336999A

AU2336999A - Method of forming concrete floors

Info

Publication number: AU2336999A
Application number: AU23369/99A
Authority: AU
Inventors: L. Joe Scallan; Arthur Sherrer Jr.
Original assignee: TECTONICS INTERNAT CORP
Current assignee: TECTONICS INTERNATIONAL Corp
Priority date: 1999-01-21
Filing date: 1999-01-21
Publication date: 2000-08-07
Also published as: IL144474A0; CN1352721A; KR20010092469A; WO2000043613A1

Description

WO 00/43613 PCT/US99/01409 METHOD OF FORMING CONCRETE FLOORS Field of the Invention 5 The present invention relates generally to methods of forming concrete and more specifically relates to methods of forming concrete floors in multiple story buildings. Background of the Invention 10 Various methods have been used to form concrete floors in multiple story buildings. Most often the forms for a concrete floor are supported either by scaffolding assembled on the floor below or a system of trusses raised from the lower floor. Thus, a new floor cannot be installed until the concrete of the lower floor, which has been 15 designed to support the slab above has cured sufficiently to support the weight of the scaffolding or truss in addition to the weight of the upper floor. This usually requires a 100 percent cure of the lower floor. Scaffolding or other post-shore supports may also be required on one or more floors lower than the floor immediately beneath the floor being poured, thus precluding the performance of other work from other trades on these floors 20 until the supports can be removed. In addition, each of the floors usually must be made thicker in order to support during construction the weight of the upper floors. The thicker floors in turn require thicker columns which must now bear the weight of the thicker floors. Each of these factors tends to increase construction times and costs and reduces the usable space in the building. 25 Summary of the Invention The present invention is directed to a method of forming concrete floors in a building comprising the steps of coupling a plurality of first form supporting shoring 30 jacks to a plurality of first columns of the building and supporting a first form on the first WO 00/43613 PCTIUS99/01409 2 shoringjacks. Then a height of the first form is adjusted at each of the first shoring jacks to attain a desired position of an upper forming surface of the first form and concrete is poured onto the upper forming surface of the first form and allowed to cure for a predetermined amount of time. Thereafter, the first form is lowered away from the cured 5 concrete. Brief Description of the Drawings Fig. 1 shows a side view of a flying form for use with a method according 10 to a first aspect of the invention supported between columns of a building; Fig. 2 shows an overhead view of the flying form of Fig. 1 in position between the columns of the building; 15 Fig. 3 shows a side view of a shoring jack for supporting the flying form of Fig. 1; Fig. 4 shows an alternative shoring jack for supporting the flying form of Fig. 1; 20 Fig. 5 shows a cross-sectional view of a column of the building with two tapered through hole forming pins received therethrough; Fig. 6 shows a side view of a through hole tapered forming pin as shown 25 in Fig. 5; Fig. 7 shows a cross-sectional view of a column of the building with a shoring jack supporting anchor mounted within the column; 30 Fig. 8 shows a perspective view of the shoring jack mounting anchor of Fig. 7; WO 00/43613 PCT/US99/01409 Fig. 9 shows a bracket and mounting plate for mounting to a column a shoring jack for supporting a flying form; Fig. 10 shows a perspective view of a shoring clip for coupling a shoring 5 jack to the bracket of Fig. 9; Fig. 11 shows a front view of the shoring jack of Fig. 10 mounted on the bracket of Fig. 9; 10 Fig. 12 shows a side view of the bracket shoring jack of Fig. 11; Fig. 13 shows a side view of a form pulling mechanism for use in conjunction with the method according to the present invention; 15 Fig. 14 shows a side view of the form pulling mechanism in position coupled to a flying form; Fig. 15 shows a form as in Fig. 1 with a bulkhead defining an outer perimeter of the floor to be poured; and 20 Fig. 16 shows a form for creating a drop beam or spandrel beam. Detailed Description 25 As shown in Fig. 1, a flying form 1 for use with the present invention includes trusses 2 which supports an upper surface 4 on which a plurality of stringers 6 are mounted. The trusses 2 are mounted to I-beams 8 which rest on and are supported by a plurality of flying form shoring jacks 10 which, in an operative position, are mounted to columns 12 of the building. 30 As shown in Fig. 2, the width W of the forms 1 is selected to be WO 00/43613 PCT/US99/01409 4 substantially equal to a separation between the columns 12 so that, when the flying form 1 is supported on the shoring jacks 10. the upper surface 4 comprised of plywood sheets 16 substantially covers the space between the columns 12. The snug fit between the width W of the forms I and the separation of the columns 12 also helps ensure that the 5 forms 1 do not fall off of the shoring jacks 10 after being placed thereon. The plywood sheets 16 are mounted on a plurality of stringers 6 which are, in turn, mounted on a nailer 17 which is bolted to the truss 2. A series of filler joists 14 are then extended between adjacent forms 1 resting on an exposed portion of the nailer 17 and plywood filler strips 18 are mounted on the filler joists 14 to create a substantially continuous forming surface 10 between the forms 1. The shoring jacks 10 are then adjusted to level the upper surface of the plywood sheets 16 and plywood filler strips 18 at a height corresponding to a lower (underside) surface of the floor 19 being poured. This allows the creation of a monolithic pouring surface for the concrete. After the floor 19 has been poured and cured to the extent that it can properly support its own weight, the forms 1 are lowered away from the 15 floor 19 and removed. Those skilled in the art will understand that this may be done when the concrete is approximately 65 to 75% and most preferably when the concrete is at least approximately 67% cured. As shown in Fig. 3, a first shoring jack 10 for use with the current 20 invention includes a bracket 20 including bolt holes 22 which, when the shoring jack is anchored to the column 12, receive anchoring bolts 52 therein. When mounted to the columns 12, each of the shoring jacks 10 abuts the column 12 with a supporting rod 26 extending vertically upward from the bracket 20. A cap 28 is secured within a corresponding recess 30 formed in an upper surface of the supporting rod 26 with a 25 washer 32 received therebetween. In addition, a roller 34 is mounted to the bracket 20 with an axis of rotation of the roller 34 extending substantially perpendicular to a surface of the column 12. The supporting rods 26 are threadedly received in the shoring jacks 10, 10' so that rotation in a first direction of a supporting rod 26 relative to the shoring jack 10, 10' raises the supporting rod 26 and the cap 28 relative to the shoring jack 10, 10' and 30 rotation in a second direction lowers the supporting rod 26 and the cap 28. When the supporting rod 26 is lowered to a lower-most position, the cap 28 is positioned below the WO 00/43613 PCT/US99/01409 5 roller 34 and the form 1 is supported on the roller 34. As shown in Fig. 4, an alternative shoring jack 10' may include 2 rollers 34 and 34' onto which the form 1 may be lowered. Specifically, by lowering all of the supporting rods 26 on which a particular form I is supported to the lowermost position, the form 1 may be rolled out of the forming position 5 on the respective rollers 34, 34' through the use of a form pulling mechanism described in detail hereafter in reference to Figs. 13 and 14. As shown in Figs. 5 and 6, the shoring jacks 10 and 10' are mounted to the columns 12 by means of through holes 40 which are formed in the columns 12 by taper 10 pins 42, which may preferably be tapered, placed before the columns are poured in locations to which the shoring jacks 10, 10' are to be attached. Those skilled in the art will recognize that if the pins 42 are made tapered as shown in Figs. 5 and 6, these pins 42 may more easily be removed from the columns 12 by impacting the smaller diameter end 44 thereof to drive the pin 42 from the through hole 40. Thereafter, anchoring bolts 15 52 for coupling the shoring jacks 10, 10' to the columns 12 are passed through the through holes 40 and coupled to the shoring jacks 10, 10'. Alternatively, as shown in Figs. 7 and 8, when it is not acceptable or permitted to create through-holes in the columns, shoring jack mounting brackets 50 are positioned within the columns 12 as they are poured so that, when the columns 12 are cured, the brackets 50 are positioned where 20 the shoring jacks 10, 10' are to be mounted with bolt receiving holes 54 exposed to the outside of the columns 12. Of course, those skilled in the art will understand that the bolt receiving holes 54 may extend from the surface of the column 12 or be recessed therein so long as the holes are open to the outside of the columns 12. These brackets may be used where through holes in columns are not permitted or acceptable. 25 Figs. 9 - 12 show an alternative arrangement for mounting shoring jacks 10, 10' to the columns 12. Specifically, a mounting plate 62 includes 2 bolt holes 64 and a bracket receiving slot 66. When assembled in an operative configuration, the bracket 60 is slid through the bracket receiving slot 66 so that an end plate 68 of the bracket 30 contacts a rear surface of the mounting plate 62. In addition, anchoring bolts 52 are extended through the column 12 to mount the mounting plate and the bracket 60 to the WO 00/43613 PCT/US99/01409 6 column 12. Thereafter, a shim clip 70 is bolted to a shoring jack 10 or 10' via bolt holes 72 and this assembly is slid onto the bracket 60 via slot 74 formed in the shim clip 70 and a set screw 76 is engaged to lock the shim clip/shoring jack assembly in place on the bracket 60 while a clip 78 maintains the shoring jack 10 in a vertical position and couples 5 the assembly to the racket 60. This arrangement allows the shoring jack 10, 10' to be positioned a predetermined distance from the columns 12. Those skilled in the art will understand that these shim clip assemblies allow a user of the flying forms according to the present invention to efficiently and safely support the flying form even where the spacing between adjacent columns varies. For example, the shim clip 70 allows a user to 10 mount a shoring jack 10 to a column recessed with respect to other columns in a particular line so that this shoring jack 10 extends further from the recessed column to align with the shoring jacks 10 mounted, for example, directly to the non-recessed columns in the line, so that the I-beams 8 are properly supported by the shoring jacks 10. 15 Figs. 13 and 14 show a form pulling mechanism 80 which is used to remove the forms I when the desired amount of concrete cure has been achieved. Initially, the supporting rods 26 of all of the shoring jacks 10, 10' are lowered until the I beams 8 are resting on the rollers 34. Thereafter, the form pulling mechanism 80 is mounted at an end 84 of the floor 19' immediately below the form I to be removed with 20 an anchor bar 82 received over the end 84. The mechanism 80 also includes a support 86 extending from the anchor bar 82 to a handle 88 and a winch 92 is mounted at the juncture of the handle 88 and the support 86. In addition, rollers 90 are mounted on ends of both the support 86 and the anchor bar 82. As shown in Fig. 14, when in an operative position, the anchor bar 82 is dropped around the end 84 of the floor 19' with the cable 94 25 from the winch 92 extending to a first end 1' of the form 1. The winch 92 then retracts the cable 94 and draws the form 1 across the rollers 34 toward the form pulling mechanism 80. As the second end 1" of the form 1 is moved out past the end of the building, the form 1 is attached via cable 96 to a crane (not shown) so that the form 1 can be lifted out and moved to the next desired location. 30 Of course, those skilled in the art will understand that the shape of the WO 00/43613 PCT/US99/01409 7 forms 1 may be altered to achieve any desired shape of the outer perimeter for the floor 19 or, as described below in regard to Fig. 15, that bulkheads may be placed along the form 1 to delimit any desired perimeter. For example, in order to achieve a floor 19 with a curved outer perimeter, the forms 1 may be formed with outer edges forming portions of 5 this curved perimeter. In addition, if it is desired to create an angled floor (such as in a parking garage ramp), this may be done by simply adjusting the heights of the various supporting rods 26 to place the forms I at the desired angle. In addition, those skilled in the art will understand that cantilevered floors may be created by simply choosing a form 1 with a length extended beyond that of the lower floor 19' or an entire form 1 may be 10 cantilevered out by, for example, resting the form 1 on underslung I-beams 8 extended from the interior of another form 1 which is mounted between the an outermost pair or row of columns 12 and an inner row of columns 12. Fig. 15 shows a form 1 with a bulkhead 112 held in place by the brace 114 15 may be extended along the forms 1 to delimit any desired perimeter of the floor 19 while the remaining portion of the forms 1 serves as a walkway 116 with a guard rail 118 installed therearound. Fig. 16 shows a flying form 100 designed to create a drop beam 102 or 20 spandrel beam. The form 100 includes a first steel beam 104 which rests on and is supported by the shoring jack 10 with a second steel beam 106 coupled to a portion of an upper surface of the first steel beam 104 by an angle brace 105. Specifically, the first steel beam extends past an outer end 106' of the second steel beam 106. Joists 108 of the form 100 which rest on the upper surface of the second steel beam 106 and on the upper 25 surface of the portion of the first steel beam 104 extending past the end 106', support a plywood forming surface 110 as in the form 1 with a first portion 110' of the forming surface 110 above the extended portion of the first steel beam 104 being a predetermined distance lower than a second portion I 10" of the forming surface 110 supported by the second steel beam 106. Those skilled in the art will understand that the distance by 30 which the first portion of the forming surface 110' is elevated above the second portion of the forming surface 110" will be substantially equal to the thickness of the beam 104. A WO 00/43613 PCT/US99/01409 8 substantially vertical bulkhead 112 is installed a predetermined distance from the end of the second portion 110" of the forming surface 110 with the distance between the bulkhead 112 and the end of the second portion 110" being substantially equal to a desired thickness of the drop or spandrel beam 102. The bulkhead may be braced as 5 shown in Fig. 15 by a wedge of plywood 114 (or dimensioned lumber such as 2x4s) mounted to the first portion 110' of the forming surface 110 with a portion of the first portion 110' extending beyond the plywood wedge 114 forming a walkway 116. A guard rail 118 may then be provided at the end of the first portion 110' of the forming surface 110". 10 Those skilled in the art will understand that the process of installing and removing the flying form 100 is substantially identical to that of the flying form 1 except that, when the form 110 is in the operative position, the supporting rod 26 must be extended further so that, upon removal, the form 110 may be lowered by an amount 15 sufficient to allow the second portion 110" of the forming surface 110 to clear the bottom of the drop or spandrel beam 102 (i.e., greater than the vertical distance between the first and second portions 110', 110" of the forming surface 110). The method of forming a concrete floor according to the present invention 20 begins with the forming and pouring of the footings of the building after which the forms for the columns 12 are prepared with pins 42 installed at each location at which sores 10, 10' are to be coupled to the columns 12. The columns 12 are then poured and, when the columns 12 have set, the pins 42 are removed and shoring jacks 10 or 10' are anchored to the columns 12 by anchoring bolts 52 which are passed through the holes left by the pins 25 42. Then the height of the supporting rods 26 is adjusted to the desired level. Meanwhile, each of the flying forms 1 or 100 is assembled by, e.g., placing two pre-drilled I-beams 8 parallel to each other on the ground and placing trusses 2 on the I-beams 8 with anchoring holes thereof aligned with each other, bolting the 30 trusses 2 to the I-beams 8 and bolting the nailer 17 to the trusses 2. Then the stringers 16 are nailed to the nailer 17 and the plywood sheets 16 are nailed to the stringers 16 and the WO 00/43613 ~ PCTIUS99/01409 9 completed form 1 or 100 is lifted into position resting on the shoring jacks 10, 10'. Then the supporting rods 26 and the caps 28 are readjusted to their exact desired positions by rotating the adjusting screws 27 and filler joists 14 are nailed to 5 exposed portions of the nailers 17 of adjacent forms 1 or 100. Thereafter, filler strips 18 are nailed to the filler joists 14 and, if necessary, bulkheads 112 are installed after which reinforcing steel, plumbing and electrical are installed and the concrete is poured. Columns 12 are then formed and poured on top of the newly poured floor 10 19 and the process of installing flying forms 1, 100 and pouring the floor 19 are repeated for the floor above. When the concrete is sufficiently cured, the adjusting screws 27 are turned with a wrench to lower the supporting rods 26 until the forms 1, 100 are resting on the rollers 34. The flying forms 1, 100 are then either pushed out of the building or pulled out using the form pulling mechanism 80 and cables are attached between a crane 15 and the forms 1, 100 to lift the forms 1, 100 to the next floor they will form, resting on newly installed shoring jacks 10, 100. The foregoing embodiments are illustrative in nature and are not intended to be limiting. There are many alternatives and variations of this method which will be 20 apparent to those skilled in the art. These variations are considered to be encompassed within the teachings of this invention, the scope of which is to be limited only by the claims appended hereto.

Claims

1. A method of forming concrete floors in a building comprising the steps of: coupling a plurality of first form supporting shoring jacks to a first plurality of columns of the building; supporting a first form on the first shoring jacks; adjusting a height of the first form at each of the first shoring jacks to attain a desired position of an upper forming surface of the first form; pouring concrete onto the upper forming surface of the first form; allowing the concrete to cure to a desired degree; and lowering the first form away from the concrete after the concrete has cured to the desired degree.

2. The method according to claim 1, further comprising the steps of: coupling a plurality of second form supporting shoring jacks to a second plurality of columns of the building; supporting a second form on the second shoring jacks; adjusting a height of the second form at each of the second shoring jacks to attain a desired position of an upper forming surface of the second form; wherein the step of pouring concrete onto the upper forming WO 00/43613 PCTIUS99/01409 11 surface of the first form includes pouring concrete onto the upper forming surface of the second form; and after the concrete has cured to the desired degree, lowering the second form away from the cured concrete.

3. The method according to claim 2, wherein the first plurality of columns and the second plurality of columns have at least one column in common and, when supported on the first and second shoring jacks, respectively, the first and second forms are positioned adjacent to one another separated by a gap approximately the width of one column, the method further comprising the step of mounting at least one filler strip across the gap to create a substantially continuous surface from the upper forming surface of the first form to the upper forming surface of the second form.

4. The method according to claim 1, further comprising the step of: positioning within the forms for the first columns a plurality of taper pins positioned in locations corresponding to the desired anchoring points for the first shoring jacks; pouring the concrete for the columns; after the concrete of the columns has cured to a desired level, removing the pins to create a plurality of holes extending through the columns at the anchoring points; and bolting the first shoring jacks to the columns by means of anchoring bolts passed through the holes.

5. The method according to claim 4, wherein the pins are tapered and wherein the pins are removed from the columns by impacting a smaller end of each of the WO 00/43613 PCTIUS99/01409 12 pins to drive a larger end of each of the pins from the corresponding column.

6. The method according to claim 1. wherein each of the shoring jacks includes a form supporting surface and a mechanism for raising and lowering the form supporting surface to desired heights.

7. The method according to claim 6, wherein each of the shoring jacks includes a roller and wherein, when the form supporting surface of each of the shoring jacks is lowered into a form removal position, the form rests on each of the rollers.

8. The method according to claim 7, wherein the step of lowering the first form away from the concrete includes the step of rolling the first form on the rollers out of the building.

9. The method according to claim 6, wherein before the first form is supported on the first shoring jacks, the height of the supporting surfaces of each of the shoring jacks is adjusted to approximately attain the desired position of the upper form surface of the first form and wherein the step of adjusting the height of the first form at each of the first shoring jacks is performed after the first form has been supported on the first shoring jacks and is employed to more precisely attain the desired position of the upper forming surface of the first form.

10. The method according to claim 1, further comprising the step of positioning a bulkhead around a predetermined portion of the first form to delimit at least a portion of a desired outer perimeter of the floor.

11. The method according to claim 8, wherein the step of rolling the first form out of the building is performed with a form rolling mechanism.

12. The method according to claim 1, wherein the first form is supported only by the columns and not by a floor beneath the first form. WO 00/43613 PCT/US99/01409 13

13. The method according to claim 3, wherein the steps recited for each of the first and second forms are repeated for at least three forms so that an entire floor of the building can be formed with a single pour of concrete.

14. The method according to claim 1, wherein when it is desired to form a cantilevered floor, the length of the first form is selected to extend past an outer edge of a floor immediately below the floor to be formed by the first form.

15. The method according to claim 1, wherein the upper forming surface of the first form include first and second portions with the first portion being higher than the second portion.

16. The method according to claim 1, wherein the desired degree of cure for the concrete is between 65 and 75% cure.

17. The method according to claim 16, wherein the desired degree of cure for the concrete is at least approximately 67% cure.

18. A method of forming horizontal surfaces in multiple storey buildings comprising the steps of: forming at least portions of vertical columns of the buildings; coupling to the columns a plurality of supports for at least one horizontal form; supporting at least one horizontal form on the supports; and pouring a predetermined amount of concrete onto an upper surface of the form to form a horizontal concrete surface.