Reinforcing net structure for geotechnical applications, use of the reinforcing net structure, and a method for production of the reinforcing net structure

Abstract

A product for reinforcing terrain includes a net structure made of a plastic material having a plurality of bars and a plurality of elongate elements that are transversal with respect to the bars. The elongate elements are arranged between adjacent pairs of bars and exhibit a substantially wire-like structure, with a transversal section having a smaller area than a transversal section of the bars. Also described are a use of the product and a method for manufacture thereof.

1 . A product for reinforcing terrains, comprising a net structure made of a plastic material, the net structure having:
 a plurality of bars, reciprocally distanced; and   a plurality of elongate elements which are transversal of the bars, the elongate elements being arranged between adjacent pairs of bars and being terminally fixed to the adjacent pairs of bars,   wherein a plurality of the elongate elements exhibits a substantially wire-like structure with a transversal section having a smaller area than a transversal section of the bars, the elongate elements being able to flex freely about at least a first and at least a second direction which are perpendicular to one another and transversal with respect to a longitudinal development direction of each elongate element.   
     
     
         2 . A product for reinforcing terrains, comprising a net structure made of a plastic material, the net structure having:
 a plurality of bars, reciprocally distanced; and   a plurality of elongate elements which are transversal of the bars, the elongate elements being arranged between adjacent pairs of bars and being terminally fixed to the adjacent pairs of bars,   wherein a plurality of the elongate elements exhibits a substantially wire-like structure with a transversal section having a smaller area than a transversal section of the bars, the elongate elements being able to flex freely about at least a first and at least a second direction which are perpendicular to one another and transversal with respect to a longitudinal development direction of each elongate element,   wherein each elongate element exhibits a transversal section having an area of less than 5 mm 2 ,   wherein the elongate elements exhibit an aspect ratio, defined as a ratio of between a square of the length of each elongate element and a mean area of the transversal section of the elongate element, which is greater than 20000, and   wherein the transversal section of the bars has a flattened conformation with an area comprised between 9 and 15 mm 2 .   
     
     
         3 . The product of  claim 1 , wherein the length of each of the elongate elements arranged between two adjacent bars is comprised between 150 mm and 300 mm. 
     
     
         4 . The product of  claim 3 , wherein length of each of the elongate elements arranged between two adjacent bars is comprised between 230 and 240 mm. 
     
     
         5 . The product of  claim 1 , wherein each of the elongate elements is substantially rigid to traction, wherein a plurality of elongate elements is arranged between two adjacent transversal bars, which plurality of elongate elements is substantially equal in length in order to define a relative maximum distance at which two adjacent bars can be positioned, and wherein thanks to the flexibility of the elongate elements given by each elongate element exhibiting a transversal section having an area of less than 5 mm 2 , adjacent bars are substantially freely positionable in a plurality of different relative positions within said maximum distance. 
     
     
         6 . The product of  claim 1 , wherein the length of each of the elongate elements arranged between two adjacent bars is comprised between 150 mm and 300 mm. 
     
     
         7 . The product of  claim 1 , wherein each elongate element exhibits a transversal section having an extension D 1  in a first direction which is greater than or equal to an extension D 2  of the transversal section in a second direction such that a ratio between the extension in the first direction and the extension in the second direction is comprised in an interval of from 1 to 3. 
     
     
         8 . The product of  claim 1 , wherein each of the elongate elements, at least in a central tract thereof being 80% of the longitudinal extension thereof, exhibits a substantially constant transversal section area, and wherein each of the elongate elements exhibits terminal portions having a transversal section with a progressively growing area starting from the central tract up to a connecting end to a bar of two adjacent bars, the product exhibiting a plurality of bars from each of which bars extend elongate elements on each of the two opposite flanks of the bars. 
     
     
         9 . The product of  claim 1 , wherein two adjacent bars are connected by at least 40 longitudinal elements per linear meter of bar, wherein the elongate elements, in absence of external loads, are arranged substantially parallel to one another. 
     
     
         10 . The product of  claim 2 , wherein two adjacent bars are connected by at least 40 longitudinal elements per linear meter of bar, wherein the elongate elements, in absence of external loads except gravity, are configured to take a position where they result parallel to one another. 
     
     
         11 . The product of  claim 1 , wherein the elongate elements exhibit an aspect ratio, defined as a ratio of between a square of the length of each elongate element and a mean area of the transversal section of the elongate element, which is greater than 20000. 
     
     
         12 . The product of  claim 11 , wherein the bars exhibit an aspect ratio, defined as a ratio between the square of the length of the bar and a mean area of the transversal section of the bar which is at least 5 times greater than the aspect ratio of the elongate elements. 
     
     
         13 . The product of  claim 1 , wherein the elongate elements exhibit an aspect ratio, defined as a ratio of between a square of the length of each elongate element and a mean area of the transversal section of the elongate element, which is comprised between 40000 and 80000; and wherein the bars exhibit an aspect ratio, defined as a ratio between the square of the length of the bar and a mean area of the transversal section of the bar, which is at least 8 times greater, than the aspect ratio of the elongate elements. 
     
     
         14 . The product of  claim 1 , wherein the transversal section of the bars has a flattened conformation with an area comprised between 7 and 15 mm 2 . 
     
     
         15 . The product of  claim 5 , wherein when two adjacent bars are arranged at a maximum distance condition from one another, substantially equal to the length of the elongate elements arranged between the two adjacent bars, wherein the adjacent bars and the corresponding elongate elements between adjacent bars are arranged such as to define a plurality of through-openings; and wherein when adjacent bars are in the said maximum distance condition, a frontal area of the through-openings is comprised in a range of between 75% and 95% with respect to a frontal area occupied by the product in its entirety. 
     
     
         16 . The product of  claim 1 , wherein the elongate elements are terminally fixed to adjacent bars by hot-coupling such as to define joining zones in which the plastic material of the elongate elements is co-penetrated into the plastic material of the bars, defining a monolithic product made of plastic material, in which the elongate elements are obtained by uni-directional longitudinal stretching, following the coupling thereof to the bars, in which the elongate elements are stretched by at least 500% with respect to an initial length thereof. 
     
     
         17 . The product of  claim 1 , wherein the elongate elements are made from a first polymer material and wherein the bars are made from a second polymer material which is different to the first polymer material. 
     
     
         18 . Method of consolidating terrains, comprising applying the product of  claim 1  to a surface zone of a front of a slope and wherein applying comprises one in the group of:
 folding the product on itself once or more times, in order to define a multilayer structure, and applying this latter to the terrain to be consolidated, and 
 applying a plurality of the products in reciprocal superposing relation and forming a multilayer structure for consolidation of terrains. 
 
     
     
         19 . A process of producing a product of  claim 1 , comprising steps of:
 forming a plurality of the bars;   forming a plurality of elements located transversally to the bars;   hot-welding distanced zones of the elements at corresponding join zones provided on adjacent bars; and   uni-directionally stretching the elements in order to form the elongate elements,   wherein the bars and the elements are formed and joined continuously by hot extrusion of the bars and contemporaneous formation of the elements transversally to the bars in order to define a monolithic semi-finished workpiece in a grid form, and wherein the elements, brought to a temperature of above 80° C., are stretched by at least 500% in order to form the elongate elements.