Abstract: In order to laminate a fabric to a plastics material grid formed of oriented strands connected by junctions having thicker and non-oriented or less-oriented nodes, the fabric and the grid having the same melting temperature, the grid is heated by a drum to melt the surfaces of the nodes, and the grid and the fabric are passed through a nip formed by nip rollers, the fabric having been pre-heated by passing around a preheat roller. One nip roller has surface protuberances formed by knurling of such a size that a number of protuberances engage (by way of the fabric) each node of the grid.

Abstract: A reinforced civil engineering structure is formed by embedding in soil one or more horizontal layers of a flexible, integral, plastics material mesh structure having oriented strands and transverse members with relatively large mesh openings. In the mesh structure, the orientation of the strands penetrates into the zones of the intersections of the strands and transverse members but the intersection zones have portions which are unorientated or substantially less orientated than the mid-points of the strands. The mesh structure has been formed by stretching a sheet of starting material having a thickness of not less than 1.5 mm and a pattern of holes whose centers lay on a square or rectangular grid, the stretching being parallel to one of the axes of the grid. The soil engages in the mesh openings, and the mesh structure provides good slip resistance properties and good stress transmission paths.

Abstract: In order to produce high tensile strength mesh structures, starting material, which is at least 0.75 mm thick and which has a square or rectangular pattern of holes or depressions, is stretched either in one direction or in two directions at right angles. The uniaxially stretched structure has orientated strands which are connected by parallel bars, the orientation of the strands penetrating into the bars but the centers of the bars being thicker than the strands, all along the length of the bar center. The biaxially stretched structure has orientated strands which are interconnected by orientated junctions which have orientated crotches between the strands; the thinnest parts of the junctions are not less than 75% of the thickness of the strands, the thickest parts of the junctions are thicker than the thinnest parts and thicker than the strands, and the center of the junction is not the thinnest part of the junction.

Abstract: In order to produce high tensile strength mesh structures, starting material, which is at least 0.75 mm thick and which has a square or rectangular pattern of holes or depressions, is stretched either in one direction or in two directions at right angles. The uniaxially stretched structure has orientated strands which are connected by parallel bars, the orientation of the strands penetrating into the bars but the centers of the bars being thicker than the strands, all along the length of the bar center. The biaxially stretched structure has orientated strands which are interconnected by orientated junctions which have orientated crotches between the strands; the thinnest parts of the junctions are not less than 75% of the thickness of the strands, the thickest parts of the junctions are thicker than the thinnest parts and thicker than the strands, and the center of the junction is not the thinnest part of the junction.

Abstract: Waisted holes are used when stretching a perforated starting material to form a mesh structure having molecularly-orientated strands. The holes define strand-forming zones which have a center part of greater width than end parts; orientation is initiated in the end parts and travels towards the middle until the whole of the strand-forming zone has been stretched out to form a molecularly-oriented strand. In the molecularly-orientated strand, there are three portions in which the middle of the strand has moved away from the ends of the strand during stretching the same distance as the edges of the strand, these portions corresponding to the end and center parts; in between, the middle of the strand has moved away from the respective end during stretching a different distance to the edges of the strand.

Abstract: In order to produce a biaxially orientated mesh structure using a single axis draw, a plastics material starting material has parallel, side-by-side main zones separated by lines of holes or depressions; the starting material is drawn parallel to the main zones, stretching the main zones into continuous, orientated main strands 4 interconnected by smaller cross-section strands 6 which have been formed from the zones between holes or depressions in each line, and have been orientated at right angles to the direction of drawing by the effect of the main zones decreasing in width as they were stretched. The mesh structure is suitable for cross-lamination.

Abstract: In order to produce a biaxially orientated mesh structure using a single axis draw, a plastics material starting material has parallel, side-by-side main zones separated by lines of holes or depressions; the starting material is drawn parallel to the main zones, stretching the main zones into continuous, orientated main strands 4 interconnected by smaller cross-section strands 6 which have been formed from the zones between holes or depressions in each line, and have been orientated at right angles to the direction of drawing by the effect of the main zones decreasing in width as they were stretched. The mesh structure is suitable for cross-lamination.

Abstract: An integral plastics material starting sheet has a square or rectangular pattern of holes defining strand-forming zones. The strand-forming zones are formed with depressions with the sheet at a low or ambient temperature. The sheet is then stretched to form the strand-forming into orientated strands.

Abstract: Plastics material mesh structures are made by providing a starting material having a pattern of primary holes or depressions and smaller secondary holes or depressions between the primary holes or depressions and stretching the plastics material to orientate the zones between adjacent holes or depressions to form orientated strands. A first stretch in a single direction produces intermediate structures having first mesh openings and smaller second mesh openings. A subsequent stretch at right angles to the first stretch produces structures having main orientated strands interconnected by shorter orientated strands arranged in such a way that only three strands meet at any junction.

Abstract: In order to provide uniaxially-stretched and biaxially-stretched mesh structures which allow for different specific designs of the interconnecting strands, a special punching pattern is used to provide holes in the starting material. The starting material has a "square" pattern of large holes. Further holes are added. These further holes can be small holes which are staggered and in pairs. When the starting material is stretched, the uniaxially-stretched structure has transverse bars interconnected by highly orientated strands each of which forks at both ends into further highly orientated strands, providing a structure which is particularly suitable for soil reinforcement. When the structure is stretched in the direction at right angles to form a biaxially-stretched structure, the zones of the bars which are between aligned strands remain as unorientated or partly orientated junctions. The remaining zones of the bars are stretched out to form highly orientated strands.

Abstract: Plastics material mesh which has spaced, longitudinal, oriented strands is used to form a retainer construction for retaining fill in a geotechnical structure. Triangular compartments are formed by having a number of parallel elongate portions of the mesh and interconnecting them by zig-zag portions, each zig-zag portion thus being mainly contained between the two respective elongate portions, and being joined to the adjacent zig-zag portion at respective corners of the compartments. The connections are made by transversely bending the strands of one portion to form loops which project out the opposite side of the other portion, and passing a connecting member through the loops to prevent the loops being pulled back.

Abstract: In order to make a non-planar plastics material article, a starting material has at least one ring of holes or depressions and is pressed so that the part which is within the ring is moved generally at right angles to the plane of the ring with respect to the part which is outside the ring, thereby stretching, into orientated strands, zones between adjacent holes or depressions in the ring; in the finished article, the strands interconnect the two parts.

Abstract: In order to produce high tensile strength mesh structures, starting material, which is at least 0.75 mm thick and which has a square or rectangular pattern of holes or depressions, is stretched either in one direction or in two directions at right angles. The uniaxially stretched structure has orientated strands which are connected by parallel bars, the orientation of the strands penetrating into the bars but the centers of the bars being thicker than the strands, all along the length of the bar center. The biaxially stretched structure has orientated strands which are interconnected by orientated junctions which have orientated crotches between the strands; the thinnest parts of the junctions are not less than 75% of the thickness of the strands, the thickest parts of the junctions are thicker than the thinnest parts and thicker than the strands, and the center of the junction is not the thinnest part of the junction.

Abstract: The plastics material device has a plurality of generally quadrilateral openings for receiving and gripping the containers. The openings have their sides formed by strips and each of the strips of two opposite, corresponding sides of each opening are orientated along their length, the strips of the remaining two opposite sides not being substantially orientated. The strips, at least, have substantial elasticity.

Abstract: In order to form an improved junction which is less liable to tear under shock loads, a diamond pattern of holes (or depressions) is formed in plastics material sheet. The holes are then in two sets of parallel lines each making an angle to the subsequent stretching direction and the holes are also in parallel rows at right angles to the stretching direction. The sheet is stretched so that the zones between adjacent holes in each line form orientated strands and the zones between adjacent holes in each row form junctions which have their lateral zones orientated but have a central zone which is unorientated or less orientated, i.e. which is thicker. The central zone can extend into two opposite crotches or be completely surrounded by highly orientated lateral zones.