EP2067907B1 - Method and spacer for fixing reinforcement mats - Google Patents

Abstract

The spacer (1) has a fixing element (2) e.g. screw, fixing reinforcing mats (3) and including a head (9). A retaining opening (5) and an insertion opening (17) are provided for the reinforcing mats. The retaining opening is formed in such a manner that an insertion direction of the reinforcing mats in the retaining opening corresponds with an insertion direction of the fixing element in the insertion opening. The retaining opening is formed in such a manner that the retaining opening prevents rotation of the spacer around a longitudinal axis. An independent claim is also included for a method for fixing reinforcing mats using a spacer.

Description

The invention relates to a spacer for fastening reinforcing mats with the features of the preamble of claim 1 and a method for fastening reinforcing mats with the features of the preamble of claim 9.

Such spacers are used to attach reinforcing mats a certain distance from an existing substrate. For example, a protective layer of shotcrete is applied to a concrete wall, which should protect the concrete wall from direct flame exposure in case of fire. The reinforcement mat serves to stabilize the shotcrete layer. Reinforcement mat is generally understood to mean a braid consisting of wires, wherein the rods can be connected to one another as mats.

From the publication DE 299 14 315 U1 Such a spacer is known. The spacer is U-shaped, with an open towards its yoke side receiving opening for inserting a reinforcement mat. The receiving opening is designed so that the inserted reinforcement mat clamped and the reinforcement mat with clamped spacer to a substrate, such as a wall, can be placed. The spacer can be used as a drilling template, with the yoke serves as a guide. After inserting the borehole in the wall, a fastener is introduced, which bears against the yoke of the spacer and covers the receiving opening to prevent detachment of the spacer from the reinforcing mat. The disadvantage is that the spacer can be solved during assembly, in particular by a twisting during drilling, from the clamped position and finally fall down. As a result, a costly rework is necessary.

The document US 6,363,679 B1 shows a spacer with a screw as a fastener for attaching reinforcing mats on a support structure. The spacer has a receiving opening for a reinforcing mat and an insertion opening for the screw. The receiving opening is designed such that the insertion direction of the reinforcing mat in the receiving opening coincides with the insertion of the screw into the insertion opening. After insertion of the reinforcement mat in the receiving opening, the screw is inserted into the insertion opening and screwed into the support structure, wherein the head of the screw covers the reinforcement mat and fixed in the receiving opening.

The object of the invention is to propose a spacer and a method with which a simple, safe and cost-effective installation of reinforcing mats is possible.

This object is achieved by the features of claim 1 and claim 9. The spacer according to the invention has a receiving opening for a reinforcing mat and an insertion opening for a fastening element. The fastening element can be, for example, a bolt anchor, nail anchor or a screw, wherein the fastening element has a head whose diameter is greater than its shaft diameter. The receiving opening is designed such that the insertion direction of the reinforcing mat into the receiving opening coincides with the insertion direction of the fastening element into the insertion opening. For example, the receiving opening may be formed as a groove which is located on the outside of the spacer opposite to the insertion direction. It is also conceivable that instead of a groove one or more bodies for receiving the reinforcing mat are mounted on the outside of the spacer. The receptacle can be designed so that an inserted rod of the reinforcing mat is clamped. This is possible for example by a V-shaped narrowing of the groove from its open to its closed end.

So that the spacer can be used as a drilling template in through-hole mounting, the spacer according to the invention has an insertion opening with a recess for drilling dust absorption. If the spacer is pressed during the drilling process as a drilling template against the ground so that it rests flat, so the drill must still be able to be removed from the hole. Otherwise, the well will clog and the fastener can not be properly introduced. Through the recess for Bohrmehlaufnahme it is possible that the drill dust can be received in the recess or discharged through the recess to the outside. A trouble-free drilling process is guaranteed and a through-hole mounting possible. From the spacer according to the invention also segment-like parts are cut out so that the drill dust can be discharged to the outside via the recess. The cutting of segments creates undercut surfaces, resulting in a positive connection between spacer and the subsequently applied shotcrete. If concrete is applied to the spacer, the undercut surfaces will be enclosed by the concrete in a form-fitting manner. The spacer gives the concrete additional support.

In a preferred embodiment of the spacer according to the invention, the receiving opening is designed so that it prevents a rotation of the spacer about its longitudinal axis with inserted reinforcement mat. By longitudinal axis is meant the axis of the spacer, which is parallel to the insertion direction of the fastener. This rotation can be realized by a line storage of the reinforcing rod through the receiving opening, or by the formation of the receiving opening by two point bearings, which are mounted at a sufficiently large distance from each other. This ensures that the holder can not turn around its longitudinal axis in shock. If the spacer is used as a drilling template for creating a hole for through-hole mounting of the fastener, prevents the rotation, that the spacer twisted by the rotational movement of the inserted into the insertion hole drill, is released from the plate and is finally torn from its position. Thus, it is possible to attach the reinforcement mat with spacers attached to a substrate and bring the necessary hole in the ground, the spacer serves as a template. The drill is for this purpose passed through the insertion opening. The holding device in combination with the anti-rotation device prevents the spacer from being detached from the reinforcing mat by the forces caused by vibrations and the drilling process. Through the hole thus created, the fastener can now be introduced and the reinforcing mat permanently fixed at a defined distance from the ground with the spacer.

Advantageously, the receiving opening has a holding device for holding the reinforcing mat. The holding device prevents the inserted into the receiving reinforcement mesh unintentionally detached from the spacer. For example, a slot shaped as a receiving opening barbs that allow easy insertion of the reinforcing mat, a movement in the opposite direction, out of the receiving opening, but prevent. The holding device acts as a captive. This ensures that the spacer can be attached to the reinforcing mat before the reinforcing mat is in its final position in which it is to be attached to a substrate.

Advantageously, the spacer has a plurality of receiving openings. For example, they may be designed so that the spacer can accommodate two mutually orthogonal wires of a reinforcing mat. As a result, a positioning of the spacer is possible directly at the intersection of two wires of a reinforcing mat, wherein both wires are inserted into the receiving openings of the spacer. The advantage of this positioning of the spacer is that no movement of the spacer in the plane of the reinforcing mat or a rotation of the spacer about the axis of the inserted wire is possible. This ensures that the required for an entire reinforcement mat variety of spacers can be factory pre-assembled without having to be laboriously repositioned before mounting on site.

A further preferred embodiment provides that the receiving opening is designed such that a plurality of mats are receivable. This can be a shock of two reinforcing mats are realized, the spacer serves as a connecting element between the mats. An additional connection of the mats with wires or special connectors is therefore superfluous, whereby labor and material is saved. In addition, it is thus possible to accommodate two intersecting but superimposed wires.

If the fastener is inserted through the insertion hole in the hole, the user must be able to easily check whether the Fastener is inserted correctly. Ideally, there is the possibility of a visual setting control. A further embodiment of the spacer according to the invention therefore provides that the insertion opening is designed such that it receives the head of the fastener so that the outer contour of the head is flush with the outer contour of the spacer. For example, a so-called nail anchor or a concrete screw with a flat, flat head is used. In the case of the spacer according to the invention, after proper installation, the head of the fastening element and the spacer together form a plane facing away from the substrate. A wrong set fastener would protrude above this level. The user knows by this possibility of visual inspection immediately, whether the setting process is completed or not.

Advantageously, the insertion opening is designed such that the head of the fastener after proper installation prevents a displacement of the reinforcing mat in the longitudinal direction and out of the receiving opening out. For this purpose, the diameter of the head of the fastener is so matched to the position of the receiving opening that it covers the receiving opening on its side facing away from the substrate at least partially after proper installation, whereby the fastener holds the reinforcing mat form-fit in the receiving opening.

After proper installation of the reinforcement mat shotcrete is applied, with a certain thickness of the shotcrete layer should not be undershot. In order to give the user an easy way of checking whether the layer thickness is sufficient, another preferred embodiment of the spacer according to the invention has a receptacle for a marker or a marker. The common length of the marker and the spacer in the longitudinal direction of the spacer corresponds to the required layer thickness of the concrete. Apply enough concrete until the marker and the spacer are concealed by the concrete and no longer visible. Of course, it is also conceivable that the spacer itself is designed so that it takes over the function of the marker.

The invention will be explained in more detail with reference to an embodiment.

Figur 1

einen erfindungsgemäßen Abstandshalter mit Befestigungselement und eingelegter Bewehrungsmatte in einer perspektivischen Darstellung; und

Figur 2

einen erfindungsgemäßen Abstandshalter mit eingelegter Bewehrungsmatte und Befestigungselement nach dem Einsetzen in einem Bohrloch in einer Seitenansicht.

Show it:

FIG. 1

a spacer according to the invention with fastening element and inserted reinforcement mat in a perspective view; and

FIG. 2

a spacer according to the invention with inserted reinforcement mat and fastener after insertion in a borehole in a side view.

FIG. 1 shows a spacer 1 according to the invention with fastening element 2 and reinforcing mat 3. The reinforcing mat 3 is formed from wires 4. The spacer 1 has receiving openings 5, which are formed as grooves. The receiving openings are arranged on the upper side 6 of the spacer 1, which is opposite to the insertion direction of the fastening element 2. The receiving openings 5 form for the wires 4 of the reinforcing mat 3 line-like supports that prevent rotation of the spacer 1 about its longitudinal axis L. As holding means 7 barbs 8 are executed, which narrow the cross section of the receiving opening 5 so that the wires 4 of the reinforcing mat 3 can be easily inserted into the groove-shaped receiving opening 5, an inadvertent removal of the spacer 1 of the reinforcing mat 3 but is excluded. The receiving openings 5 intersect at a right angle, so that the spacer 1 at the point of intersection of two wires 4 of the reinforcing mat 3 can be fixed so that the point of intersection coincides with the intersection of the two receiving openings 5. The depth T of the groove-shaped receiving opening 5 is chosen so that it corresponds to a multiple of the diameter D of the wire 4. This makes it possible to accommodate a plurality of wires 4 in a receiving opening 5 and so perform a shock of reinforcing mats, or to record the mat at a crossing point of the wires 4. The fastening element 2 has a head 9 whose diameter is greater than the diameter of the shank 10 of the fastening element 2 and is larger than the insertion opening 17 ( FIG. 2 ). The head 9 of the fastener 2 covers the receiving openings 5 such that the reinforcing mat 3 is held in a form-fitting manner in the receiving opening 5. On the upper side 6 of the spacer 1, a cylindrical pin is arranged as a marker 11, which may be made in one piece with the spacer 1, or as shown here, is connected by a non-visible support with the spacer 1. The spacer 1 has on its lower side 12 a recess 13 which serves as Bohrmehlaufnahme. In addition, segment-like parts are cut out of the spacer 1, so that the drilling dust can be discharged to the outside via the recess 13. The cutting of segments creates undercut surfaces 19 resulting in a positive connection between spacer 1 and the subsequently applied shotcrete 14, which FIG. 2 can be seen.

FIG. 2 shows the spacer 1 in the installed state. In the receiving openings 5 of the spacer 1, a reinforcing mat 3 is inserted so that a crossing point of two wires 4 of the reinforcing mat 3 is received by the spacer 1. The holding devices 7 hold the reinforcing mat 3 in the receiving opening 5. The inserted into the receiving opening 5 reinforcing mat 3 prevents rotation of the spacer 1 about its longitudinal axis. The spacer 1 can now be applied with an inserted reinforcement mat 3 to a substrate 16 and a borehole 15 are introduced into this substrate 16, wherein the insertion opening 17 of the spacer 1 serves as a drilling template. Then, the fastener is introduced into the borehole 15. The introduced fastener 2 secures the spacer 1 and thus the reinforcing mat 3 permanently. The head 9 of the fastener 2 prevents by positive locking that the reinforcing mat 3 can slip out of the receiving opening 5. The Outer contour of the head 9 of the fastener 2 is flush with the outer contour of the upper side 6 of the fastener 2, whereby the user is signaled that the fastener 1 is set properly. The borehole 15 is introduced into the substrate 16, for example concrete. After installation of the spacer 1 with reinforcing mat 3 and fastener 2 shotcrete 14 is applied to the substrate 16. The height H of the spacer 1 with attached marker 11 corresponds to the required thickness of the shotcrete layer 14. If the shotcrete 14 is applied so that the tip 18 of the marker 11 is no longer visible, this signals to the user that the shotcrete 14 is applied in sufficient thickness is.

LIST OF REFERENCE NUMBERS

1

spacer

2

fastener

3

reinforcement mat

4

wire

5

receiving opening

6

upper side of the spacer 1

7

holder

8th

barb

9

Head of the fastener 2

10

Shaft of the fastener 2

11

markers

12

lower side of the spacer 1

13

recess

14

shotcrete

15

well

16

underground

17

insertion

18

Tip of the marker 11

19

undercut surface

Claims (14)

1. Spacer (1) having a fixing element (2) for fixing reinforcing mats (3), having an accommodating opening (5) for a reinforcing mat (3) and having an insertion opening (17) for the fixing element (2), the fixing element having a head (9) and the accommodating opening (5) being so constructed that the direction of insertion of the reinforcing mat (3) into the accommodating opening (5) is the same as the direction of insertion of the fixing element (2) into the insertion opening (17),
   characterised

   - in that the insertion opening (17) has a recess (13) for accommodating drill dust,

   - in that segment-like parts are cut out from the spacer (1) so that drill dust can be conveyed towards the outside by way of the recess (13), and

   - in that, as a result of the cutting-out of the segment-like parts, the spacer (1) has undercut surfaces for formation of a positive connection with shotcrete.
2. Spacer according to claim 1, characterised in that the accommodating opening (5) is so constructed, as a result of formation as a linear mounting for a reinforcing rod (4) or as a result of formation of two point mountings for the reinforcing rod (4), that the inserted reinforcing mat (3) prevents the spacer (1) from twisting about its longitudinal axis.
3. Spacer according to claim 1 or 2, characterised in that the accommodating opening (5) has a holding device (7) for holding the reinforcing mat (3).
4. Spacer according to one of claims 1 to 3, characterised in that the spacer (1) has a plurality of accommodating openings (5).
5. Spacer according to one of claims 1 to 4, characterised in that the accommodating opening (5) is so constructed that a plurality of reinforcing mats (3) are accommodatable.
6. Spacer according to one of claims 1 to 5, characterised in that the insertion opening (17) is constructed in such a manner that it accommodates the head (9) of the fixing element (2) so that the outer contour of the head (9) is flush with the outer contour of the spacer (1).
7. Spacer according to one of claims 1 to 6, characterised in that the insertion opening (17) is constructed in such a manner that the head (9) of the fixing element (2) at least partly covers over the accommodating opening (5) so that displacement of the reinforcing mat (1) in the longitudinal direction of the spacer (1) and out from the accommodating opening (5) is preventable as a result of the head (9) of the fixing element (2).
8. Spacer according to one of claims 1 to 7, characterised in that the spacer (1) has a marker (11) for marking a prespecified thickness of the shotcrete (14).
9. Method of fixing reinforcing mats (3) using a spacer (1) according to one of claims 1 to 8, characterised in that the reinforcing mat (3) is introduced into the accommodating opening (5) and is held in the accommodating opening (5) by means of a holding device (7); in that the reinforcing mat (3) inserted into the accommodating opening (5) prevents the spacer (1) from twisting about its longitudinal axis; in that the spacer (1), with the reinforcing mat (3) inserted, is then placed against a substrate (16), and a drill hole (15) is introduced into that substrate (16), the spacer (1) serving as a drilling template; and in that the fixing element (2) is introduced into the drill hole (15) for lastingly fixing the spacer (1).
10. Method according to claim 9, characterised in that the spacer (1) is positioned at the crossing point of two wires (4) of the reinforcing mat (3).
11. Method according to claim 9 or 10, characterised in that the outer contour of the head (9) of the fixing element (2) is flush with the outer contour of the spacer (1) as an insertion check.
12. Method according to one of claims 9 to 11, characterised in that the head (9) of the fixing element (2) at least partly covers over the accommodating opening (5) so that displacement of the reinforcing mat (3) in the longitudinal direction of the spacer (1) and out from the accommodating opening (5) is prevented.
13. Method according to one of claims 9 to 12, characterised in that shotcrete (14) is applied in an amount such that a marker (11) mounted on the spacer (1) is covered by shotcrete (14) and is no longer visible.
14. Method according to one of claims 9 to 13, characterised in that shotcrete (14) is applied to the spacer (1) and the reinforcing mat (3) in such a manner that the shotcrete (14) surrounds undercut surfaces (19) of the spacer (1).

Images