EP0351668B1 - Dowel for façades - Google Patents

Description

The invention relates to a facade dowel in the form of an elongated connecting element for installation in mutually aligned bores of a supporting wall and a facade arranged in front of it at a distance from a ventilation gap, the connecting element emitting an axial channel extending from its rear end for mortar injection with a plurality of radial openings adjoining it in the facade area contains in the annular space formed with the borehole wall, the ends of which are closed in the area of the facade by lamellae which can be fixed on the connecting element, and the axial channel also contains an outlet opening for the injected mortar mass in the supporting wall area.

It is known to connect the facing wall, facing shell or facades arranged at a distance in front of the main wall or supporting wall to the supporting wall using Z-shaped bent iron, also called air-layer anchors. Such anchor bars protrude, for example, from an opening in the supporting wall and are mortared or concreted in with their free end in a mortar joint or another receptacle of the curtain wall. Over time, the anchor iron extending through the ventilation gap between the facade and the supporting wall rust through and then no longer meet the safety requirements, so that the facade in the course of changes in elongation caused by temperature differences.

A known from the DE-A 1 802 770, Fig. 5, facade dowel of the type mentioned has the shape of a bolt-shaped connecting element for bridging the ventilation gap between the facade and the supporting wall. The axial channel extending through the connecting element is closed at the preceding end and is provided with radial channels extending from it both in the facade area and in the supporting wall area, which open out at the periphery of the connecting element into outlet openings for the injected mortar mass. Since the bolt-shaped connecting element is made of solid material with a narrow axial channel, it is not able to adapt to the relative movements between the facade and the supporting wall that occur during weather and temperature changes. This has the consequence that the connecting elements loosen relatively quickly and / or breaks occur in the facade. In addition, the known connecting element can only be used in conjunction with a low-viscosity synthetic resin, because a mortar applied with cement and sand cannot escape sufficiently from the narrow channels and openings and cannot fill the annular space between the connecting element and the wall hole.

The invention has for its object to improve and further develop a facade anchor of the type specified in such a way that it can advantageously replace the so-called air-layer anchors described above by having a small diameter the wall holes, for example corresponding to a normal mortar joint width, nevertheless a complete mortar filling also ensures that the wall hole furthest away from the injection point and, moreover, also ensures their permanent bond in the event of relative movements between the facade and the supporting wall.

• das Verbindungselement ist ein aus korrosionsbeständigem Stahl bestehendes dünnwandiges Dübelrohr, dessen vorangehendes Ende die im Tragwandbereich mündende Austrittsöffnung bildet;
• das Dübelrohr ist an mehreren Stellen seiner Länge durch parallel zu seinem Umfang verlaufende, insbesondere diametral zueinander angeordnete Paare von Sicken oder Kerben gegen unkontrollierte Knickung versteift und gleichzeitig gegenüber Relativbewegungen von Fassade und Tragwand begrenzt nachgiebig;
• zur zentrischen Positionierung sind auf dem Dübelrohr im Bereich der Ein- und Ausgänge der Wandbohrungen befestigbare nachgiebibe Lamellen dichtungen tragende Kunststoffbuchsen angeordnet.

To achieve this object, the facade dowel has the following features according to the invention:

• the connecting element is a thin-walled dowel tube made of corrosion-resistant steel, the preceding end of which forms the outlet opening which opens into the supporting wall area;
• the dowel tube is stiffened at several points along its length by pairs of beads or notches running parallel to its circumference, in particular diametrically arranged to one another, against uncontrolled kinking and at the same time is flexible to a limited extent with respect to relative movements of the facade and supporting wall;
• For centric positioning, flexible bushings that carry gasket-bearing plastic bushings are arranged on the dowel tube in the area of the entrances and exits of the wall bores.

With this design, the thin-walled, corrosion-resistant dowel tube is sufficient due to the high tensile and bending strength of its material and due to its mortar bond with the wall holes, all forces that may occur between the supporting wall and the facing shell or facade due to settlement or expansion. Since the required tensile and bending strength is guaranteed even with a small wall thickness of the dowel tube, there is a sufficient cross-section inside as a flow channel available for the mortar to be injected, even if the outer diameter of the dowel tube is reduced to such an extent that it can be inserted into wall bores that do not exceed the dimensions of a conventional mortar joint and outside the dowel tube there is still a sufficient distance for the mortar bond between Dowel tube and borehole wall remain. The beads or notches attached at longitudinal intervals prevent an uncontrolled kinking of the dowel tube and give it a certain flexibility at these points, which may be desirable in the area of the ventilation gap with regard to possible expansion movements between the supporting wall and the facing shell. The small wall thickness and the resulting large cross-section of the injection channel lead to the advantage that the dowel tube can be accommodated in a hole within a conventional wall joint during renovation work and undesirable additional facade holes can be largely avoided. The plastic bushings, which bear the resilient lamella seals, ensure that the dowel tube is held centrally within the wall bores at least until the mortar has set, so that a secure bond with the borehole wall is created over the entire circumference of the dowel tube.

The preferably diametrically opposite pairs of openings provided in the facade area of the dowel can be dimensioned such that the mortar injected through the dowel tube initially flows through the unimpeded pipe cross-section to the open end due to the lower resistance and fills the borehole from there, while the pressure continues to build up the mortar gradually emerges from the circumferential openings and fills the annular space in the facade area which is closed off by the lamellar bushings. The mortar crosspieces located inside and outside the dowel tube, which connect the mortar masses to one another, form through the openings.

To achieve the controlled bending ability of the dowel tube, it is proposed that the beads or notches of the dowel tube are arranged in pairs in the same radial plane and in an axial sequence offset by 90 ° to each other. The beads or notches in the dowel tube can preferably be provided in the area of the ventilation gap. The outer circumference of the dowel tube is expediently roughened and / or provided with grooves similar to a thread in order to improve the mortar bond between the dowel tube and the borehole wall.

In a further embodiment of the facade dowel according to the invention it is proposed that the plastic bushings each consist of a jacket surrounding the dowel tube with a plurality of ring-shaped or helical lamellas facing the borehole wall, and that at least one radially directed knob is formed on the inside of the jacket, which is formed in an opening of the dowel tube can be pressed in to fix the socket.

To simplify assembly on the dowel tube, the plastic bushings can contain a longitudinal slot which also extends through the molded knobs. Due to the elasticity of the plastic material forming the bushes, these automatically attach themselves to the circumference of the dowel tube. Since the longitudinal slot also extends through the knobs, this gets a certain flexibility, with which it can be easily pressed into the assigned opening in the dowel tube and then widened again. The lamellae of the plastic bushings can expediently contain a V-shaped recess at least on the side opposite the longitudinal slot, which facilitate the opening of the bushing and are effective for venting the wall bores during the mortar injection.

The lengths of the plastic bushings or the lamellar spacing can be dimensioned such that they cover wall areas which have broken out around the entrance or exit of the wall bores and lie against the undamaged borehole wall with at least two lamellas.

According to a further feature of the facade dowel according to the invention, a stocking made of plastic fabric can be pulled over the preceding end of the dowel tube and is clamped to the dowel tube in the area of the lamella group that closes the supporting wall bore. In this way, when the dowel is inserted into a hollow brick, the escape of the mortar is limited and a gradual pressure build-up is achieved in the partially permeable stocking, so that the mortar escapes from the openings in the dowel tube in the facade area.

• Fig. 1 einen schematischen Längsschnitt durch einen Fassadendübel gemäß einer Ausführungsform der Erfindung in eingebautem Zustand in Bohrungen einer Hauptwand und einer Vormauer,
• Fig. 2 einen vergrößerten Längsschnitt durch eine Lamellenbuchse als Abdichtung für den Ringraum zwischen Dübelrohr und Bohrlochwand,
• Fig. 3 einen um 90° bezüglich Fig. 2 gedrehten Teilschnitt der Lamellenbuchse,
• Fig. 4 eine Endansicht der Lamellenbuchse nach Fig. 2 und
• Fig. 5 einen schematischen Längsschnitt durch einen Fassadendübel gemäß einer zweiten Auführungsform der Erfindung in eingebautem Zustand.

Embodiments of the facade dowel according to the invention are explained below with reference to the drawings. Show it

• 1 shows a schematic longitudinal section through a facade dowel according to an embodiment of the invention in the installed state in bores in a main wall and a facing wall,
• 2 shows an enlarged longitudinal section through a lamella bushing as a seal for the annular space between the dowel tube and the borehole wall,
• 3 shows a partial section of the lamellar bushing rotated through 90 ° with respect to FIG. 2,
• Fig. 4 is an end view of the lamellar bushing according to Fig. 2 and
• 5 shows a schematic longitudinal section through a facade dowel according to a second embodiment of the invention in the installed state.

Between a main or subsurface wall 10 and a curtain wall 12, which is shown schematically in vertical section in FIG. 1, there is a ventilation or insulating gap 26, which is usually used for rear ventilation of the facade and can optionally be filled with insulating material. A bore 16 extends through the facade 12 and is aligned with a bore section 14 in the underground wall 10. Preferably the hole corresponds approximately to the thickness of a normal mortar joint of 12 to 15 mm, although other dimensions are also possible. For larger dimensions, if the mortar joint or areas next to it have to be drilled out, the broken-out wall areas 18 and 20 shown in FIG. 1 can arise at the entrance and exit of the facade bore.

A dowel tube 22, preferably made of thin-walled stainless steel, is inserted into the prepared bores 14, 16 and extends with its preceding end 23 into the vicinity of the bottom of the borehole 15. As a facade dowel, the dowel tube 22 carries a total of three lamella bushes 24 made of resilient material or plastic, which serve as a concentric end plug for the mortar mass to be filled. Each lamella bushing 24 consists of a jacket 32 which bears against the outside of the dowel tube and from which annular lamellae 34 point in the radial direction. The lamellae 34, which can optionally also be helically formed on the casing, are supported on the wall of the boreholes 14 and 16 and are then effective as a seal against the mortar mass injected through the dowel tube.

Preferably, at the end preceding in the direction of the borehole, an inwardly directed extension or knobs 36 is formed on the inside of the lamella bushing, which has a circular circumference, for example, in the enlarged illustration according to FIG. 3. A positioning opening 38 is assigned to each knob in the dowel tube, into which the knob 36 is pressed and thereby the lamellae is positioned in the axial direction. The position of these openings 38 in the dowel tube can be adapted to the conditions given by the respective wall.

It can be seen from FIG. 1 that a lamellar bushing 24 closes off the annular space around the dowel tube at the entrance of the borehole 14 into the underground wall. The next following lamella bush 24 is located on the back of the facade wall 12, i. H. on the inside of the ventilation gap 26, where it closes off the annular space around the dowel inside the facade wall, which on the other hand is closed at the front by the lamella bushing arranged at the borehole entrance to the facade wall. The length of the lamellar bushes 24 is dimensioned such that wall areas which have broken out around the entrance and exit are also taken into account and in any case two lamellas lie sealingly against the undamaged borehole wall.

The dowel tube 22 is open at both ends. 1, the dowel tube 22 can be made flexible at various points, preferably in the area of the ventilation gap by transverse beads or notches 40, which are preferably arranged in pairs on opposite sides and are also offset in pairs by 90 ° to one another. In order to achieve a particularly effective bond between the facade wall, mortar mass and dowel, the circumference of the dowel tube 22 can be roughened or grooved as a whole or only in the facade area.

There are also several in the area of the facade Pairs of mutually opposite openings 28, 30 in the dowel tube, through which the mortar exits into the annular space between the dowel tube and the borehole wall after the borehole 14 in the underground wall has been filled and a pressure has built up. After the mortar has hardened, extending transverse webs or breaking webs are formed through the dowel tube 22, which are connected to the filling compound in the annular space and serve to transmit the holding force.

3 and 4, the lamella bushing 24 is provided with a longitudinal slot 42. Advantageously, there is a V-shaped recess 46 in each of the lamellae 34 on the side opposite the longitudinal slot in order to facilitate the opening of the lamellae bushing. Additional V-shaped recesses 44 may be provided to facilitate air leakage from the borehole when the backfill is injected

According to FIG. 5, a drill hole 16 is made in the mortar joint between two stones of a facade wall 12 in need of renovation and a blind hole 14 in the underlying substrate by means of a hammer drill. After the boreholes have been cleaned of the drilling dust and moistened, an injection tube, preferably made of plastic parts, is then put together and inserted into the aligned boreholes. The injection tube comprises a plastic tube 54 for bridging the ventilation gap 26 and a rear plastic sleeve 62, which are inserted into one another and inserted into the borehole until they are one defined dimension are pressed into the facade bore 16.

The plastic pipe 54 has at the preceding end 56 outer sealing lamellae 58 which prevent the mortar from escaping from the wall bore 14. The plastic pipe is extended beyond the penetration depth of the sealing lamellae, so that, similarly to the steel pipe described above, a molded network can be clamped on using a plastic ring, with which the function is also ensured with hollow bricks, perforated or honeycomb bricks. The total length of the plastic tube 54 depends on the ventilation gap 26 and extends beyond the length of the ventilation gap by a certain amount into the borehole 14 in the underground wall or into the borehole 16 of the facade wall.

The rear end 60 of the plastic tube 54 is inserted into a receptacle 68 surrounded by outer sealing lamella 64 at the preceding end of the plastic sleeve 62 inserted into the facade bore. The sealing lamellas 64 delimit the cavity filled with mortar and delimited to the outside by the borehole wall in the facade wall in the direction of the ventilation gap 26. At the rear end of the plastic sleeve 62 near the entrance of the borehole 16 there are sealing lamellas 66 on the outer circumference and in the area between In the preceding slats 64 and the rear slats 66, the plastic sleeve 62 contains a plurality of longitudinal slots 70 through which the mortar exits into the outer annular space at the latest after the borehole 14 in the underground wall has been completely filled and an increased pressure has built up.

The plastic tube 54 is preferably press-fitted into the receptacle 68 of the plastic sleeve 62 and locked there by a stop shoulder. The plastic sleeve 62 can contain a total of four longitudinal slots 70. After the mortar injection has been completed, an anchor element in the form of a wire anchor 50 is introduced into the injection tube, which can have at least one widened nail head 52 at the preceding end. If the dimensions permit unobstructed mortar injection, the wire anchor 50 can also be inserted into the wall bores together with the injection pipe made of plastic. The mortar is z. B. pressed into the borehole by means of a funnel, wherein it passes through the annular gap between the wire anchor and Injection tube penetrates the holes and fills them. The material bond between the mortar and the supporting substructure creates a material composite that is essential for anchoring. When using a molding net, this is stretched through the penetrating mortar, so that a force-locking connection is created by forming the borehole. The annular space between the wire anchor and the inner wall of the plastic tube is preferably small.

Reference symbol list

10th

- underground wall

12

- Facade

14

- Drill hole in the underground wall

16

- Drill hole in the facade

18th

- Wall breakout at the entrance of 16

20th

- Wall breakout at the exit from 16

22

- anchor tube

23

- previous pipe end

24th

- Lamellar bushing

26

- ventilation gap

28, 30

- diametrical pairs of openings in anchor tube

32

- Jacket 24 sleeve

34

- slats

36

- inner neck or pimples

38

- Positioning opening in the anchor tube for 24

40

- Stiffening beads, cross notches

42

- Longitudinal slot in 24

44, 46

- V-shaped recesses in the slat circumference

48

-

50

- anchor element

52

- thickened headboard

54

- Plastic tube to bridge the air gap

56

- previous end

58

- circumferential lamellas on 56

60

- rear end of the plastic tube

62

- plastic sleeve

64

- Slats at the previous end of 62

66

- fins at the rear end of 62

68

- Locating hole for rear end of 54

70

- Longitudinal slots in 62

Claims (9)

1. Facade tie having the form of an elongated connecting element (22) for fitting into mutually aligned bore holes (14, 16) of a support wall (10) and of a facade (12) arranged in front thereof by the distance of an aeration gap (26), wherein the connecting element (22) includes an axial duct for mortar injection extending from its rear end and communicating with a plurality of radial openings disposed in the facade area for mortar discharge into the annular space formed together with the bore hole wall, the ends of said annular space being sealed in the facade area by lamellae (34) adapted to be fastened to said connecting element (32), said axial duct having a discharge opening for the injected mortar also in the area of the support wall,
   characterized by following features:

   - the connecting element is a thin-walled tie pipe (22) consisting of corrosion-resistant steel, the preceding end (23) of which forming the discharge opening in the area of the support wall;

   - the tie pipe (22) at several places along its length is reinforced against uncontrolled buckling by substantially diametrically arranged pairs of corrugations or identations (40), which run parallel to its circumference, and additionally is of limited resiliency in view of relative movements of the facade (12) with respect to the support wall (10);

   - plastic material bushings (24) bearing lamellae seals (34) are set on the tie pipe (22) for its central positioning in the area of the entrances and exit (18, 20) of the wall bore holes (14, 16).
2. Facade tie according to claim 1, characterized in that the corrugations or identations (40) of the tie pipe (22) are provided as pairs in the same radial plane and at axial sequences at 90% offset to each other.
3. Facade tie according to claim 1 or 2, characterized in that the corrugations or identations (40) of the tie pipe (22) are preferably provided in the area of the aeration gap (26).
4. Facade tie according to one of the preceding claims, characterized in that the external periphery of the tie pipe (22) is roughened and/or is provided with grooves similar to a screw thread.
5. Facade tie according to one of the preceding claims, characterized in that each plastic material bushing (24) consists of a jacket (32) enveloping the tie pipe (22) and having several annular or spiralling lamellae (34), and in that at least one radial inwardly directed knob (36) is molded to the internal side of the jacket (32) and adapted to be pressed into an opening (38) of the tie pipe for adjusting the bushing (24).
6. Facade tie according to one of the preceding claims, characterized in that each plastic material bushing (24) contains a longitudinal slit (42) extending also through the molded knob (36).
7. Facade tie according to claim 6, characterized in that the lamellae (34) of the plastic material bushing (24) contain at least one V-shaped recess (46) on the side opposite of the longitudinal slit, which facilitates the straddling of the bushing and acts for ventilation of the wall bore holes (14, 16) during injection of mortar.
8. Facade tie according to one of the preceding claims, characterized in that the length of the plastic material bushings (24) or the distances between the lamellae are dimensioned such that they will cover burst open wall portions at the entrance or exit of the wall bore holes and sealingly engage the uninjured bore hole wall with at least two lamellae (34).
9. Facade tie according to one of the preceding claims, characterized in that a stocking consisting of synthetic fabric is drawn over the preceding end of the tie pipe (22) and is clamped to the tie pipe (22) at the area of the group of lamellae sealing the bore hole (14) of the support wall

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