FR2597137A1 - Bracing element for welded wire meshes - Google Patents

Abstract

A layer of three parallel wires 1, 2, 3 and of a zigzagging wire 4 welded to the latter is shaped in order to have, in cross-section, a substantially trapezoidal shape.

Description

Spacer element for welded mesh.

 The invention relates to a bracing element for welded mesh, in particular for producing concrete slabs.

 The metal reinforcement of a concrete slab is often made from welded mesh.

 When two layers of welded mesh have to be placed one above the other on site before pouring the concrete slab, their spacing is well determined and must be respected. If only one welded mesh is used, its spacing from the bottom of the formwork must also be well defined and respected.

 The object of the present invention is to provide a bracing element for welded mesh, which is easy to produce, store, transport, and implement, which is economical and sufficiently resistant.

 The subject of the invention is a bracing element for a welded trellis, characterized in that it consists of a sheet of three parallel wires and a fourth wire running in a zig-zag pattern under the first three, and welded to them, this sheet then being shaped to have a substantially trapezoidal shape in cross section.

According to other features of the invention
- before shaping, the fourth wire consists of oblique strands with respect to the first three wires, and separated by elbows placed outside the external wires
- between two elbows each oblique strand has a small section between the elbow and the first external wire, a large section between the external wire and the central wire, a large section between the central wire and the second external wire, and a small section between the second outer wire and elbow
- After shaping, only the small sections are in the initial plane of the ply of wires, the central wire and the neighboring parts of the fourth wire being in a parallel plane.

By way of example, the accompanying drawing is shown
Figure l, a flat view of a bracing element according to the invention before shaping;
Figure 2, a perspective view of a bracing element according to the invention after shaping;
Figure 3, an end view of a bracing element according to Figure 2.

 Referring to FIG. 1, it can be seen that the bracing element according to the invention consists of: on the one hand three parallel wires 1, 2, 3, and on the other hand a fourth wire 4 zigzag current under the first three, so as to always meet them at the same angle. This fourth wire consists of a series of identical strands separated in pairs by elbows 5, 6 arranged outside of the wires l and 3. In this way, each strand comprises: a small section 7 between the elbow and the outer wire, a large section 8 between the outer wire and the central wire 2, a large section 9 between the central wire 2 and the other outer wire, and a small section l, between the other outer wire and the elbow following.

 The assembly of the 4 wires is done by welding, as for a trellis. Once this assembly has been carried out, the layer of wires is shaped so that the central wire 2 is placed in a plane parallel to that of the exteriors l and 3. The bracing element thus formed is shown in perspective on Figure 2 and in end view in Figure 3. In these figures, we see that the outer son l, 3 and the small sections 7, l of the wire 4 remained in the initial plane of the web of Figure l. On the other hand, the central wire is in a plane parallel to that of the external wires l and 3. It is supported by a portion of the wire 4 which is in the same parallel plane. In FIG. 3, the bracing element appears to be shaped on an isosceles trapezoid template. The section of wire 8 of FIG. 1 corresponds to the oblique part 13 and to the horizontal part ll of the wire 4. Similarly, the section of wire 9 of FIG. 1 corresponds to the horizontal part 12 and to the oblique part 14 of the wire 4.

 It can be seen that the general shape of the bracing element according to the invention is trapezoidal, and symmetrical with respect to the vertical plane containing the central wire 2. This shape allows the elements according to the invention to be stacked for storage and transport, under reduced volume.

 The bracing element according to the invention is particularly stable due to its trapezoidal shape and its symmetry. It must be strong enough to support the weight of a man walking on the welded mesh placed on the element, while remaining light enough for reasons of economy.

 As an example, 3 mm diameter wires can be used. If, for a particular reason, we want to use wires with a larger diameter, we can use for the central wire alone a diameter of 5 mm, or else for the three longitudinal wires a diameter of up to 8 mm, for example, and for the fourth wire a diameter of 5 mm, for example.

 It can be noted that the bracing element according to the invention has many advantages: it is easy to build by automatic means; it is light and saves weight, which makes it economically competitive; it is stackable which reduces storage and transport costs and it is stable and resistant on site. Finally it can be made of smooth or notched steel wires according to the resistances to be obtained.

Claims (4)

claims.  1. Spacer element for welded mesh, characterized in that it consists of a sheet of three parallel wires <1, 2, 3) and a fourth wire (4) running in a zig-zag under the three first, and welded to them, this sheet then being shaped to have a substantially trapezoidal shape in cross section.  2. Element according to claim 1, characterized in that before shaping, the fourth wire <4) consists of oblique strands relative to the first three wires, and separated by elbows (5, 6) placed at the exterior of the exterior wires (l, 3).  3. Element according to claim 2, characterized in that between two elbows (5, 6> each oblique strand has a small section <7) between the elbow (5) and the first outer wire <1) a large section (8 ) between the outer wire <1) and the central wire (2), a large section (9) between the central wire (2> and the second external wire (3), and a small section (l) between the second external wire (3) and the elbow (6).  4. Element according to claim 3, characterized in that after shaping, only the small sections are in the initial plane of the ply of wires, the central wire (2) and the neighboring parts <11, 12) of the fourth wire <4) lying in a parallel plane.