A trellis or lattice structure which is designed to constitute fencing for gardens or is intended for decorative purposes. The trellis or lattice is comprised of elongated thermoplastic elements which are "U-shaped" in cross section and which have on each side a longitudinally extending semispherical relief or boss. The elements are also provided with transversely extending slots of a configuration corresponding to the external configuration of the elements, whereby the elements can be removably assembled by vertical or horizontal sliding engagement so as to constitute a checkerwork structure. The present invention relates, generally speaking, to trellis or lattice structures designed to constitute fencing elements for delimiting gardens or plots of land, for palisades or, alternatively, for the decoration of walls, ceilings, arches or pergolas, or for concealing a bare wall. It is known to manufacture trellis work, generally from painted timber or galvanized or plasticized iron and secured either on a wall or in equidistant posts made fast in the ground. These materials require permanent and frequently costly maintenance, the timber utilized for the manufacture of such fencing elements sometimes deteriorating at the securing points and the galvanized of plasticized iron not adequately resisting the effects of oxidation. It is one of the objects of the invention to remedy the disadvantages exhibited by these types of fencing elements and to permit the production of a trellis or lattice structure composed of multiple elements made from a thermoplastics material and arranged in chequerwork fashion, the assembly and/or disassembly thereof being capable of being readily and rapidly effected, the structure at the same time exhibiting an adequate degree of rigidity and flexibility to ensure that it shall be extremely robust. The invention also permits the provision of a trellis or lattice structure the constituent elements of which are associated with connecting elements permitting the displacement of the said constituent elements, with a view to replacing one or more of the latter. It also permits the provision of a trellis or lattice structure the constituent elements of which are able to undergo modifications as to length due to the expansion or contraction of the material employed, without detriment to the appearance of the assembly, notably in the case of a trellis or lattice structure serving for the decoration of a wall or of a panel. It also permits the provision of a trellis or lattice structure the elements for the connection of the constituent elements of which are designed in such manner as to permit a modification in the appearance of the structure as a whole. It also permits the provision of a trellis or lattice structure the profile of the constituent elements of which permits the inverting thereof at the instant of assembly and the production, with the aid of cranked angle sleeves or equivalent elements, of various decorative models. The trellis or lattice according to the present invention is characterized in that the elements of which it consists are constituted by section elements made from a thermoplastics material the cross-section of which is U-shaped and which have, on each of their lateral arms and in the longitudinal direction, a semispherical relief or boss permitting the releasable assembly thereof, by self-engagement or by vertical or horizontal sliding, with identical section elements in the lateral arms or limbs of which there are formed equidistant recesses having the same shape as that of the section elements with which they are to be releasably associated, so as to constitute a chequerwork structure which may or may not be delimited by a frame at least two of the elements of which are formed with recesses having the same shape as that of the sections. According to a special feature of the invention, the sections assembled by self-engagement with the identical sections formed with recesses in their lateral arms are adapted to be displaced by sliding in the said recesses. According to a further feature of the invention, the said sections are provided on their external face with bosses the purpose of which it is to limit their sliding in the recesses. According to yet a further feature of the invention, the frame of the trellis or lattice structure is constituted by elements having a U-profile in cross-section, at least two of the said elements having, in their inner arms or limbs, equidistant recesses of the same shape as the sections constituting the trellis or lattice. According to an advantageous mode of embodiment, the sections constituting the trellis or lattice exhibit, in cross-section, a recessed profile of rectangular or square section, the purpose of which it is to impart increased rigidity thereto. According to yet a further advantageous mode of embodiment, the sections constituting the trellis or lattice and exhibiting, in cross-section, a recessed profile of rectangular or square section, are provided with two semi-spherical reliefs arranged parallel, with a view to assembling them with two juxtaposed sections. According to a further feature of the invention, the sections constituting the trellis or lattice are conjugated with removable elements permitting the securing of the trellis or lattice on a support. According to a further feature of the invention, the profiles or sections constituting the trellis or lattice are conjugated with removable connecting elements the purpose of which it is to cover the ends of two sections between which there is provided a space permitting any expansion and/or contraction of the said sections which may result from a change in temperature. According to a further feature of the invention, the elements for framing the trellises or lattices are connected by angled connecting elements permitting the expansion and/or contraction of the said framing elements, depending on the temperature.
