EP0311876B1 - Compound for prefabricated forms - Google Patents

Abstract

Projections are provided on the clamp portion of a formwork lock. The projections are spaced from inwardly extending inclined surfaces of the claws of the clamp. The projections engage the outer sides of the corners of the flange of a formwork panel frame, while the inwardly extending surfaces on the claws engage complementary surfaces of the framework panel frame.

Description

The invention relates to a composite of two formwork panels and formlocks for element formwork according to the preamble of the main claim.

Such devices are known for example from German Patent DE-A-27 59 966.

Ready-made formwork of this type has meanwhile been differentiated into lighter formwork and heavier formwork. The lighter formwork is often called "residential formwork", which is used for concreting up to a height of 300 cm. Living rooms also have heights of around 200 cm, so that 300 cm formwork height is rather the exception here. There is also the heavier industrial and engineering formwork, which of course can also be used to form lower heights, but which can reach heights of up to 10 meters, corresponding to the higher structures in industry and engineering.

Housing formwork is usually lighter than industrial and engineering formwork. The former weighs approximately up to 40 kg / m² and the latter is above it on average. The weight differences result from the fact that in one case the profile frame and the crossbeams are less stiff and the formwork panel is somewhat thinner than the other type. You can also see the differences in the size and weight of the formwork locks: a formwork lock for residential formwork weighs on the order of 1 kg, while a formwork lock for industrial and engineering formwork weighs on the order of 3 kg.

According to the invention, this object is achieved by the features evident from the characterizing part of the main claim.

Constructively, this means that the projections e.g. In the case of the so-called mammoth formwork from the Meva company, it can only be made a fraction of a millimeter to a few millimeters higher and this dimension is also monitored as a tolerance measure in the manufacture of the formwork locks. The projections since then only had management tasks and served to strengthen the claws in the root area.

It would therefore not be sufficient if the corner surfaces were only in contact or if they were applied with too little force. Because of the material properties and the lever ratios caused by the relatively long cross members, one would quickly be above the flatness tolerance e.g. of 3 mm.

Due to the features of claim 2 it is achieved that these first areas do not evade even if the wedge gear e.g. for caution or carelessness. The term "quasi" is a term often used for labeling in mathematics and technology. See e.g. Meyers Lexicon of technology and the exact natural sciences, vol. 3, p. 2088 u. 2089.

Due to the features of claim 3, one comes close to the third area, which is favorable in terms of lever and force, so that it can take away a considerable part of the force. Nevertheless - in contrast to the conditions in the first area - one remains in the elasticity.

A measure according to claim 4 has proven very successful in the dimensions and materials used in technology, regardless of whether additional beads are provided for other purposes, for example.

Frame legs according to claim 5 are known per se and can be used without modification.

According to claim 6 it is achieved that the welding systems and the position of the weld need not be changed. It is now also able to absorb the sudden increase in compression forces.

A dimensioning according to claim 7 is sufficient to approximately double the formwork pressure that an industrial and engineering formwork can accommodate if the deflection should not be more than 3 mm at a distance of 1 m from the measuring points.

A dimensioning according to claim 8 is sufficient for the so-called mammoth formwork from Meva, Haiterbach, and for formwork related to it, such as Framax frame formwork from Doka, Munich, the Manto formwork from Hünnebeck, Ratingen, the top formwork from Noe , Sweets etc.

Due to the features of claim 9, a finer limitation of the force required is obtained.

Due to the features of claim 10 one can get down to a minimum of clamping points (two clamping points are sufficient) without e.g. the deflection increases more than 3 mm at a distance of 1 m from the measuring point. With such a low number of scarf locks, you can get by especially if you provide the scarf locks directly above or below the crossbeam.

Due to the features of claim 11, values are obtained for the housing formwork, with which one can switch only at the height required for residential buildings, which is also lighter and whose profile frame and crossbeams are also noticeably weaker.

The features of claims 12, 13 give an even better limitation of the force. Of course, higher forces are harmless, because - as with industrial and engineering formwork - the frame legs and formlocks can easily withstand higher forces.

Claim 14 teaches how little tensioning points you can get by, and here too it is favorable to provide the formlocks as close as possible to the cross member.

Claim 15 shows that the projections do not necessarily have to be provided exclusively at the root of the claws. If the projections on the steel profile of a frame leg were to be provided, this would mean at least one further set of rollers. In the case of aluminum profiles, on the other hand, the training is simpler, since the extrusion process does not matter whether there is more or less sales. If you look at the projections on the frame leg, it should be borne in mind that this creates another corner where concrete could stick despite cleaning.

Fig. 1

eine Schalung, bestehend aus dem Verbund einer Vielzahl von Schaltafeln, von außen gesehen;

Fig. 2

einen waagrechten Schnitt längs der Linie 2-2 in Fig. 1 im Maßstab 1 : 1;

Fig. 3

eine Ansicht gemäß dem Pfeil 3 in Fig. 2;

Fig. 4

den Querschnitt durch einen Aluminiumrahmenschenkel;

Fig. 5

einen schematischen Querschnitt ähnlich Fig. 2 zur Erläuterung der Wirkung der Erfindung nach Ansicht des Erfinders.

The invention will now be explained on the basis of preferred exemplary embodiments. The drawing shows:

Fig. 1

formwork, consisting of a composite of a large number of formwork panels, seen from the outside;

Fig. 2

a horizontal section along the line 2-2 in Figure 1 on a scale of 1: 1.

Fig. 3

a view according to arrow 3 in Fig. 2;

Fig. 4

the cross section through an aluminum frame leg;

Fig. 5

a schematic cross section similar to FIG. 2 to explain the effect of the invention in the opinion of the inventor.

1, a composite 11 is put together for a formwork height of 300 cm + 120 cm = 420 cm. The maximum scarf height is 420 cm.
In the lower area formwork panels 12 are provided on the left, which are 250 cm wide. You have a profile frame 13 which runs around the outside and has a vertical central web 14. In the fields between the vertical frame legs of the profile frame 13 and the central web 14, horizontal cross members 16 extend at a uniform distance. In the vertical frame legs of the profile frame 13 and in the central web 14, recesses 17 and 18 are provided for the tie rods of formwork anchors. The one another Adjacent vertical frame legs of the profile frame 13 are connected with scarf locks 19, three of which are used here. To the right, the composite 11 continues with formwork panels 21, which also have a profile frame 22. The profile frames 13 and 22 are made of the same material with the same cross section. The profile frames 22 are connected to one another and to the adjacent profile frame 13 by means of formlocks 19. All scarf locks 19 are designed in principle the same. Also in the fields of the formwork panels 21, three formwork locks are attached in height. The formwork panels 21 also have recesses 17 and 18 at the same height as the formwork panels 12 for the same purposes. The formwork panels 21 are 125 cm wide. The formwork panels 12 are formed from the formwork panels 21 in that two adjacent vertical frame legs were not connected to one another by formwork locks. Rather, they have been welded together to create an element that is twice as large in width and area. Also in the formwork panels 21, the cross members 16 run horizontally and in alignment with the cross members 16 of the formwork panels 12. On the right, the assembly 11 continues with a formwork panel 23 which is only 90 cm wide but also 300 cm high. Since it - apart from the width - has the same design as the formwork panels described above, it is not explained in detail. On the far right is a formwork panel 24 with a width of 45 cm, which does not require any further explanation.

The height of 300 cm is increased by a row of formwork panels arranged above it, whereby again formwork panels 21 can be seen which lie horizontally and are the same as the formwork panels 21 described above.
It can also be seen that they are interlocked with scarf locks 19 and with the underlying part of the assembly. Since the upper formwork panels 21 are arranged horizontally, their cross members 16 run vertically. Corresponding to the smaller height of 1.20 m, only two scarf locks 19 are used here in height. To the right are further formwork panels 26, 27 and 28, which correspond in width to the formwork panels 21, 23 and 24 arranged underneath, but are only 1.20 m high and have horizontal cross members 16. The bracketing and the arrangement of the recesses are shown in the drawing.

It is clear that the concrete pressure is at the very bottom in the composite 11. However, it is forbidden to compensate for the bulges caused by the fact that the profile frame 13 becomes too solid at the bottom or e.g. downwards to more cross beams, because then the flexibility of such a composite 11 would no longer exist, because then there would be a "bottom" and "top" in the formwork panels. The formwork panels must be designed so that considerations of this kind are not necessary.

2 and 3 each show a formwork plate 29, on the front 31 of which concrete is in contact during concreting. The formwork panels 29 are supported from the rear by the cross members 16. They are made of steel and have a hat profile. They are screwed from the rear against the formwork panels 29 by screws 30. Two frame legs 32, 33 have the same cross-section in mirror image and are made of steel.
Fig. 2 shows the cross section on a scale of 1: 1. The frame legs 32, 33 are known per se in their shape and properties as a steel beam. In the narrow formwork panel 24, the cross members 16 are hardly subjected to bending, and here the frame legs 32, 33 bear a relatively large amount of the formwork pressure. With the formwork panel 23, the cross members 16 are already subjected to considerably more bending and with the formwork panels 12, the cross members 16 are subjected to a maximum amount of bending and thus attempt to twist the frame legs 32, 33.
2, the cross members 16 are butt welded to the frame legs 32, 33 by means of weld seams 35. The frame legs 32, 33 each have a first leg 34 with an outer transverse surface 36. The first legs 34 consist of two partial legs which are butt welded to one another via a weld 40. The weld seam on the outer transverse surface 36 has been removed, so that the outer transverse surfaces 36 of both frame legs 32, 33 can be exactly aligned. Towards the middle, the first legs continue after a 90 ° bend in second legs 37, which abut one another in a mutually parallel manner. You then pass into a known nose 38, which continues on the outside of the formwork plate 29 as a third leg 39. The inner surface of the formwork plate 29 lies again on the knee 41. A fourth leg 42 follows the knee 41, which, like the other legs with the exception of a bead 43, runs in a straight line. The beads 43 of both frame legs 32, 33 are exactly opposite, since the profile is identical. Each bead 43 has a bevel 44 which is inclined towards the formwork plate 29 and also a bevel 46 which is inclined towards the first leg 34. In a base 47, the slopes 44, 46 merge into one another. Every fourth leg 42 has an outer corner surface 47 on the outside at the transition to the first leg 34, which is nothing other than the outer surface of the fourth leg 42. In the view of FIG. 2, the outer transverse surface 48 of the cross beams 16 runs by the amount above the outer transverse surfaces 36 of the first legs 34 that is necessary in order not to let the weld seam running there protrude downward.

A scarf lock 49 is made of malleable cast iron with a sigma of 800 kP (kilopond), namely sigma tension ÷ sigma pressure. At least 500 kP are necessary. The scarf lock has two claws 51, 52, each of which has at their upper, inner ends a projection 53, 54 which is directed towards each other and which has an inward and downward slope 56, 57 which is associated with the associated slope 44, 46 , which - as the drawing shows - do not need to have the same angle. The system takes place at different angles in the corner area 58, 59 with more line contact than surface contact. The corner area 58, 59 is located outside the base 45. The projection 53, 54 is also at a distance from the bevel 46 of both beads 43.

To go down, the projections 53, 54 merge into an inner surface 61, 62 which is at a clear distance from the fourth legs 42. In the area of the outer corner surfaces 47, however, the claws 51, 52 each have a projection 63, 64, the outer surface 66, 67 of which lies at 30 kN on the respective outer corner surface 47, 48. So that defined investment conditions prevail here and do not dictate the situation, for example, concrete dirt or the like, a groove 68, 69 connects to the outer surfaces 66, 67.

The corner regions 58, 59 are also under a force of 30 kN if the outer surfaces 66, 67 do so.

The scarf lock 49 has a yoke 71, consisting of a web 72 which runs parallel to the first legs 34, extends below the claw 51, has a contact surface 73 for the outer transverse surface 36 and a rectangular hole (not shown) for a wedge 74 has. The web 72 is guided in a flat guide 76 of the web 77 that is integral with the claw 51. In FIG. 2, the web 77 has an abutment surface 78 directed upwards for both the outer transverse surface 36 of the frame leg 32 and of the frame leg 33, but for the latter only little overlap a plane of symmetry 79. Rectangular holes 83 for the wedge 84 are provided in the web 77 both in its upper wall 81 and in its lower wall 82. All you need to tighten is a standard formwork hammer, which usually weighs 1 kg and slightly less. When tightening, one hits the head 84. The forces represented by the arrows 86, 87 are thus applied, the arrow 86 representing the force introduced at this point and the arrow 87 the reaction force at this point.

It turns out that everything that has been described in connection with FIGS. 2 and 3 is known, with the exception of the design of the projections 63, 64, which have been thickened so far in the direction of the plane of symmetry 79 that they are reliable and with of the necessary force there, while the corner area 58, 59 of the claws 51, 52 does not yet bump into the base 45.

2, it is readily apparent that the projections 63, 64 are of some use if, for example, with the right formwork plate 29 held in place, the left formwork plate 29 is moved clockwise, namely about a pivot axis that is in the plane of symmetry 79 is approximately in the region of the lugs 38 perpendicular to the plane of the drawing in FIG. 2. It can then be seen that the second legs 37 cannot move away from one another in such a way that a wedge-shaped gap which is open at the bottom would result.
This type of load occurs when a network is hanging and oscillating, for example on the crane.

However, if concrete pressure is to be absorbed, the force on the formwork panels 29 comes from the other side, namely from above according to FIG. 2, and since the cross members 16 have a tendency to bulge downwards, the second legs 37 want to move away in such a way that that there would be an open wedge gap. It is precisely here that the invention seeks to provide a solution, and using the fig. 5 tries to explain the effect.
5 is far exaggerated in the drawing. The frame legs 32, 33 are also only shown schematically, as is the scarf lock 19. The position shown in solid lines corresponds to that in FIG. 2. If concrete is now loaded, there is a tendency to assume the position shown in broken lines. It can be seen that this position can only be assumed if the yoke 71 is able to shorten. This is because the distance between points 88, 89 is shorter than between points 91, 92. However, if there is a hold by the forces according to arrows 87, then the position shown in broken lines in FIG. 5 cannot be assumed and the frame legs 32, 33 remain in their drawn position. Of course, the outer surfaces 66, 67 bear on the outer corner surfaces 47 under friction and a force which is explained in more detail above. As long as these conditions are met, the desired effect occurs. If the surfaces on both sides are made of steel, then you have, for example, a static friction coefficient, which is approximately equal to the coefficient of friction, of 0.20.
For aluminum / steel, the situation can be easily surveyed.

FIG. 4 shows a profile that can be used for the invention for an extruded frame leg on a scale of 1: 1 for the material Al Mg Si 0.5 F25. Here the first leg 34 is 4 mm thick according to the force acting on it. In the area of the first leg 34, the profile must be quasi stiff in the transverse direction. In the area of the slope 44, however, the fourth leg 42 must be able to yield somewhat inwards. Because of the lower modulus of elasticity compared to steel, a transverse wall 93 is provided here which, on the other hand, is supported on the second leg 37 and can deflect like a leaf spring without being permanently deformed.

The invention can also be used if the profile frame 13 e.g. are made of glass fiber reinforced plastic. The profile frame 13 can also be made of foamed plastic or foamed material, in which case instead of the discrete legs 34, 37, 39, 42 areas whose outline cannot be defined as precisely as in the exemplary embodiments, but which have the same effect.

The terms Dywidag, Framax and Manto are registered trademarks.

Claims (15)

1. Interconnected assembly (11) of two shuttering panels (12) and shuttering locks (19, 49) for prefabricated shutterings which have at least two clamping points,
   having in each case one shuttering-panel profile frame (13),
   having a multiplicity of rigid transverse load-bearing members (16) which are parallel to one another, are at approximately the same distance from one another, and the ends of which are connected rigidly to two mutually parallel frame legs (32, 33) of each profile frame (13), having in each case one shuttering board (29) which is located in front of the transverse load-bearing members (16) and is supported by them,
   having a first oblique portion (44), provided on the frame legs (32, 33) of each profile frame (13) such that it runs around on the inside, which is located nearer the shuttering board (29) than an outer transverse surface (36) of the frame leg (32, 33), increases outwards and, measured from the transverse surface (36), is at the same spacing at all points,
   having four regions of each frame leg (32, 33), the first (34) having the transverse surface (36), the second region (37) having an outer abutment surface which is at least partially at right angles to the shuttering board (29) and, if appropriate, butts against an abutment surface of the neighbouring shuttering board (29), the third region (39) extending behind the shuttering board (29) and parallel thereto, and the fourth region (42) having the first oblique portion (44) and being arranged at a distance from the second region (37),
   the first regions (34) being in alignment, and the first (34) and fourth (42) regions forming in each case a corner with an outer corner surface (66, 67) on the fourth region (42), and it being possible, in the region of the oblique portions (44), for the frame legs (32, 33) to be elastically compressed perpendicularly to the fourth region (42),
   having two claws (51, 52) and a wedge mechanism (74, 76) for each shuttering lock (19, 49), there being provided, on the regions (53, 54), of the claws (51, 52), to be directed towards one another, second oblique portions (56, 57) which interact with the first oblique portions (44) and press the neighbouring frame legs (32, 33) towards one another as well as towards the yoke (71) of the shuttering lock (19, 49),
   having a planar abutment surface (73, 78) on the inner side of the yoke (71), on which the outer transverse surfaces (36) of the frame legs (32, 33) abut, such that they are aligned at least with part-regions, and having protrusions (63, 64) on regions, to be directed towards one another, on the claw root and/or on the fourth regions (42) of the frame leg (32, 33) at the level of the outer corner surfaces (47, 48), the protrusions (63, 64) being considerably shorter than the length of the claws (51, 52) and a free space being present between the protrusions (63, 64) and the second oblique portions (56, 57),
   characterized by the following features:

   a) the outer surfaces (66, 67) of the protrusions (63, 64) butt against the respective outer corner surfaces (47, 48) of the fourth region (42),

   b) with the protrusions (63, 64) abutting according to a), the second oblique portions (56, 57) of the claws (51, 52) are still at a distance from an end position on the first oblique portions (44) of the fourth region (42), to be precise after forces have been applied onto the wedge mechanism (74, 76) by hammer blows from builders' hammers and prior to permanent deformation of the first regions (34) and of the fourth regions (42),

   c) in the mounted state, the first regions (34) have a defined first clear dimension at their outer corner surfaces (47),

   d) in the mounted state, the protrusions (63, 64) have a second clear dimension, which is equal to the first clear dimension, between their outer surfaces (66, 67) which are to be directed towards one another,

   e) the second oblique portions (56, 57) have their desired position on the first oblique portions (44).
2. Interconnected assembly according to Claim 1, characterized in that the first regions (34) are quasi non-compressible.
3. Interconnected assembly according to Claim 1, characterized in that the distance of the second oblique portions (56, 57) from the first regions (34) is more than half the width of the fourth regions (42).
4. Interconnected assembly according to Claim 3, characterized in that the distance is approximately 2/3 to 3/4.
5. Interconnected assembly according to Claim 1, characterized in that the frame legs (32, 33) consist of cold-rolled steel and form a closed profile.
6. Interconnected assembly according to Claims 1 and 5, characterized in that the first regions (40) (sic) comprise two butt-welded legs.
7. Interconnected assembly according to Claim 1, characterized in that, in the case of large-surface area shutterings with a shuttering-panel dimension from at least 250 cm (height) × at least 75 cm (width), the force on the corner surfaces (47) is between 15 and 50 kilo-newtons with two or three shuttering locks (19, 49) arranged along the height.
8. Interconnected assembly according to Claim 7, characterized in that the force is 30 ± 25% kilonewtons.
9. Interconnected assembly according to Claim 8, characterized in that the force is 30 ± 10% kilonewtons.
10. Interconnected assembly according to Claim 7, characterized in that two or three clamping points are provided along the height.
11. Interconnected assembly according to Claim 1, characterized in that, in the case of housing-construction shutterings with a shuttering-panel dimension from 250 cm (height) × at least 75 cm (width), the force on the corner surfaces is between 7 and 25 kilonewtons with two or three shuttering locks arranged at 205 cm.
12. Interconnected assembly according to Claim 11, characterized in that the force is 15 ± 15% kilonewtons.
13. Interconnected assembly according to Claim 12, characterized in that the force is 15 ± 10% kilonewtons.
14. Interconnected assembly according to Claim 11, characterized in that two or three clamping points are provided.
15. Interconnected assembly according to Claim 1, characterized in that the protrusions (63, 64) are provided partially or completely on the corner surfaces (47).

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