The PolGrid Geogrids. Soil reinforcement and stabilization.

Transcription

1 The PolGrid Geogrids Soil reinforceent and stabilization

2 The Pietrucha Group Proudly Polish, Truly International The Pietrucha Group is an efficiently anaged, copetitive and innovative group of copanies which specializes in the anufacturing and distribution of top-class geosynthetic products as well as providing a coprehensive range of geotechnical services broadly used in civil engineering. Geosynthetic products anufactured by the Pietrucha Group are delivered to nearly 30 custoers in 3 countries on 5 continents, especially in regions sensitive to the ipact of cliate change. Despite the scope and global reach of our operations, the Pietrucha Group has reained a faily business, anaged by a third generation of entrepreneurs. Advantages... How they work... 6 Technology... 8 Application... 9 Product Range Copleted projects... 1 Frequently asked questions The PolGrid geogrid used to reinforce and stabilize aggregate. 3

3 The PolGrid Geogrids Advantages The Pietrucha Group is the anufacturer of the PolGrid geogrids, specialized geosynthetics widely used in the civil engineering projects to stabilize and reinforce land or to separate the substrate layers with varying graining. Geogrids are used in transport construction projects and other geothechnical works. PolGrid products are quick and easy to install and allow for the reduction of the use of aterials, thus saving investent costs and tie. Iediate stabilization and separation Saving of costs and tie Easy and fast installation Environentally friendly solution The sei-stiff coposite aggregate schee allows for the reinforceent of aggregate, even on extreely low load-bearing surfaces. Increased load-bearing capacity owing to the rigid construction based on nonovable nods, which iediately responds to pressure, preventing aggregate shifts. Increased reinforceent of road structure preventing horizontal displaceent and penetration (propagation) of aggregate grains into the weak substrate and the loss of stability of the foundation layer. Geogrid with stiff nodes placed between the road foundations and the subsoil prevents the ixing of aterials with different grain size and load-bearing capacity. Effective blocking of the aggregate efficiently reinforces the load-bearing capacity of the structure. By decreasing the soil replaceent, geogrids allow for savings on the aggregate of up to 0. This ethod extends the durability of the structure and does not require any advanced preparatory earthwork, which reduces the construction tie span. Thanks to a better load and pressure distribution in the road foundation, geogrids considerably reduce the aount of wheel ruts, even in extreely unfavorable soil conditions. The specially adjusted width of the PolGrid sheets eans geogrid rolls can be handled by two persons. The siplified installation consists in spreading the rolls of the geogrid on the prepared soil substrate. Geogrid with stiff integrated nodes do not require pre-tensioning or anchoring, and they work iediately once they are spread on or below the aggregate layers. High endurance of the geogrids guarantees resistance to installation daage. As a result of considerable savings on the aggregate, the use of the PolGrid geogrids helps reduce the CO eissions caused by construction works. The use of the PolGrid geogrids considerably extends the life perforance of asphalt. The PolGrid geogrids have been proven to perfor in extree cliate conditions which helps reduce the road aintenance costs. 5

4 The PolGrid Geogrids How they work Blocking and horizontal fixing of aggregate Thanks to the rigid construction based on non-ovable nods, which iediately responds to pressure, the PolGrid geogrids prevent aggregate shifts. Used to reinforce the road structure, geogrids prevent horizontal displaceent and penetration (propagation) of aggregate grains into the weak substrate and the loss of stability of the foundation layer. Iediate stabilization and reinforceent of road structure The sei-stiff coposite aggregate schee allows for the reinforceent of aggregate, even on extreely low load-bearing surfaces. Blocking of the aggregate by the geogrid is a key factor during the pre-copaction of the road foundation, as well as for the further behaviour of the road in lifetie. A high elastic odulus (stiffness of geogrid) is considered to be the ain feature which enables effective restriction of oveent of the aggregate and as a result, an effective reinforceent of structure. With geogrid The square shape of rib gives better aggregate chocking in geogrid aperture than flat or rounded ribs. Without geogrid Geogrids allow for savings on the aggregate layer used to construct a given road, without any ipact to its load-bearing capacity. Separation With geogrid Without geogrid The PolGrid geogrids placed between the road foundations and the subsoil work as a separator preventing the ixing of the aterials with different grain size and load-bearing capacity. Geogrids help avoid the penetration (propagation) of aggregate into the weak substrate and the loss of stability of the foundation layer. On boggy substructures or in case of aterials of unfavourable grain size, where the separating function needs to be enhanced, geocoposites are used, i.e. geogrids cobined with s. It has been proven that over tie, geogrids considerably reduce the aount of wheel ruts, even in extreely unfavorable soil conditions. α β 6 7

5 The PolGrid Geogrids Technology The PolGrid Geogrids Application Tar roads Railways The key feature of the PolGrid products is their rigid construction with stiff and integrated nods. The structure has no interconnecting junctions and the strength of the geogrid node is equal to the strength of the rib. PolGrid is anufactured on an autoated 130 eter long technological line and it involves extruding a theroplastic polypropylene plate, then perforating the calibrated plate and finally stretching the aterial in both directions. Reinforceent of aggregate substrate layers, reinforceent of ebankents and dykes, geosynthetic layers at the base of ebankents. Reinforceent of substructures of the railway tracks, strengthening of railway ebankents. The anufacturing technology as well as the used aterials guarantee high quality of the product and its unvarying technical paraeters. Forrest roads and technological roads Teporary roads and working platfors Construction of dirt roads with extended durability and resistant to the creation of wheel-ruts. Quick construction of teporary roads ade of unbound aggregate, i.e. technological roads, access roads to windfars, working platfors. Technology partners The quality of the PolGrid geosynthetics is onitored at an in-house laboratory under the supervision of the British Textile Technology Group as well as the Süddeutsche Kunstoff-Zentru, one of the world s ost acclaied institutions certifying geotechnical products. The physio-echanical paraeters of the geogrids are subject to continuous onitoring by an in-house research center. The Pietrucha Group is also a eber of the International Geosynthetic Society. Scarps and bridgeheads Warehouses, carparks 8 Uniaxial geogrids are used in the construction of high scarps, bridgeheads and as in reinforced earthworks, i.e. construction of vertical retention walls with veneer. Reinforceent of subsoil requiring higher load-bearing capacity, i.e. under anoeuvring squares, warehouse storage yards, parking lots. 9

6 The PolGrid geogrids Product Range The diverse PolGrid product range allows for the optial selection of a given product to eet the requireents of individual projects and constructions. Depending on the functionality and the project requireents, a geosynthetic with a given coposition and for is selected. Biaxial geogrids Geogrids with stiff nods without any interconnecting junctions. In the anufacturing process, the perforated PVC plate is stretched biaxially. The onolithic construction with rectangular openings gives better support to the aggregate and allows for a considerable increase in the load-bearing capacity. PolGrid MAX Application Reinforceent of railway track substructure Reinforceent of road foundations Construction of teporary and technological roads Construction of forest roads Construction of access roads to windfars PolGrid Application Reinforceent of road substructures Construction of teporary and technological roads Construction of forest roads Construction of access roads to wind-fars Construction of parking areas Reinforceent of substructures of railway tracks Reinforceent of ebankents and dykes Reinforceent of building foundations Reinforceent of substructures under technical floors and ass storage areas Polyer type Miniu carbon black Peak tensile strength MD/CMD Junction efficiency Aperture size - MD Aperture size - CMD Length in a roll units % kn/ % MAX 0/0 0/0 65 ( 1) 65 ( 1) 75 MAX 30/30 30/30 65 ( 1) 65 ( 1) MAX 0/0 0/0 65 ( 1) 65 ( 1) 30 The size of the opening is extended to 65, intended to be used with larger graining aggregate Roll width units 10/10 15/15 0/0 5/5 30/30 0/0 5/5 Polyer type Miniu carbon black % Peak tensile strength MD/CMD kn/ 10/10 15/15 0/0 5/5 30/30 0/0 5/5 Junction efficiency % Aperture size - MD 39 ( ) 39 ( ) 39 ( ) 39 ( ) 39 ( ) 35 ( 3) 35 ( 3) Aperture size - CMD 39 ( ) 39 ( ) 39 ( ) 39 ( ) 39 ( ) 35 ( 3) 35 ( 3) Length in a roll Roll width 10 11

7 Geocoposites Geocoposites cobine the advantages of a geogrids and non-woven geofabric for even higher reinforceent, filtration and separation. Geocoposites are used on boggy substructures or together with aterials of unfavorable grain size. The type of the non-woven geofabric ay be individually selected to eet the requireents of a given project. Uniaxial Geogrid A special type of geosynthetics ade of high density polyethylene (). In the anufacturing process, the perforated plate is stretched in one direction, resulting in the final product s rigidity and strength of 0 to 160 kn/, depending on the geogrid type. Uniaxial geogrids are applied to reinforce scarps and ebankents and repair of landslides and the construction of retaining walls. PolGrid FSR Application PolGrid UX Application Reinforceent of road substructures Construction of teporary and technological roads Construction of forest roads Construction of access roads to windfars Construction of parking lots Reinforceent of railway track substructures Construction of ebankents on weak soil Reinforceent of building foundations Reinforceent of scarps, repair of landslides Anti-corrosion earthworks Reinforceent and construction of ebankent extensions Construction of bridgeheads Ebankents of water reservoirs, das and waste landfills Construction of retaining walls Geocoposite PolGrid FSR is the PolGrid or PolGrid MAX geogrid therally cobined with non-wovengeofabric. units UX 0 UX 55 UX 80 UX 90 UX 10 UX 160 GEOGRID Polyer type Miniu carbon black % Peak tensile strength MD/CMD kn/ Aperture size - MD 35 ( 0) 35 ( 0) 35 ( 0) 35 ( 0) 35 ( 0) 35 ( 0) NON-WOVEN Aperture size - CMD 16 ( ) 16 ( ) 16 ( ) 16 ( ) 16 ( ) 16 ( ) GEOFABRIC Length in a roll Roll width

8 Copleted projects Warsaw, Poland Express road S Polgrid 30/ Inczew, Poland Construction of technical roads and access roads to windfars and working platfors Polgrid 30/ Gubin, Poland Construction of a forrest road Polgrid 30/ Brzezinka Średzka, Poland Reinforceent of a railway track substructure Polgrid 30/ Głubczyce, Poland Construction of technical roads and access roads to windfars Polgrid 30/ Rzepin, Poland Geosynthetic layer under a tar road Polgrid 0/0 and Polgrid 5/

9 Chojna, Poland Modernization of forrest roads Polgrid 30/ Srokowo, Poland Construction of a DW 6 road Polgrid 30/ Łódź, Poland Reconstruction of the Stylowa Street Polgrid 30/ Kunów, Poland Construction of a teporary road during reconstruction of a railway track Polgrid 30/ Kalisz, Poland Reconstruction and reinforceent of the Wrocławska Street Polgrid FSR 0/ Rzeszów, Poland Reinforceent of an ebankent during the construction of the S19 road Polgrid 0/

10 The PolGrid geogrids Frequently asked questions What is a geosynthetic? The ISO nor defines the geosynthetic as a product of which at least one coponent is produced fro polyer (polyester, polypropylene, polyethylene or nylon), has the for of a sheet, strip or spatial for, and is used in contact with the soil (or other aterial) in geotechnical and civil engineering projects. Geosynthetics belong to a large faily of aterials with a very wide range of applications, used priarily for reinforceent, stabilization, draining, filtration, separation and preventing erosion. What are geogrids? Geogrids are a special type of geosynthetics are used in civil engineering to physically reinforce and stabilize the soil. Geogrids interlock with aggregate and thus fors a coposite. Geogrids are anufactured as openwork sheets in the shape of an orthogonal grid with high level of stiffness. PolGrid geogrids do not have any junctions (it is a onolith) and have unique features which other producers of other geogrids cannot boast. What are the functions of a geogrid? A geogrid works priarily as reinforceent, increasing the load-bearing capacity of the surface. Thanks to the use of geogrids, the structure is able to transfer increased tensile stress, like in the case of steel reinforceent in reinforced concrete structures. Geogrids also act as a separator of aterials with different grain size of load-bearing capacity, the soft subsoil and the aterial foring the structure, e.g. aggregate in the paveent of the road. It effectively prevents different particles fro ixing and, consequently, prevents deterioration of the bearing capacity of the road and perforance of the construction layers. What is the anufacturing process of geogrids? Geogrids are anufactured on a production line with the length of 130 and this technology involves extruding a theroplastic polypropylene sheet, which is then perforated and stretched lengthwise and crosswise. Carefully selected raw aterial, production paraeters and perfected technology process eans high-strength reproducible aterial can be obtained. Is technology iportant for paraeters of the geogrids? Yes, it is. There are any types of geogrids on the arket: extruded, welded or woven, which interact with soil in various ways. Many studies conducted around the world have proven that the best strengthening effect is achieved by using extruded, onolithic geogrids there is no need for pre-tensioning and anchoring of this geogrid, because due to its rigidity it works as of the oent of instantly, resulting in a shorter tie and lower costs of the construction works. In addition, they are highly resistant to daage during the laying and copaction of aggregate and the do not break even during copaction by heavy vibrating rollers. The Polgrid geogrid bears such properties. What paraeters should be used as a guide when choosing of geogrid? The ost iportant paraeters characterizing the geogrids are tensile strength in both directions, the size of the tensile force at a strain of % and 5%, the efficiency of nodes, openings size, quality of raw aterials used in anufacturing, and the CE ark with full identification. Does the apertures shape ake a difference? No, it does not. On the arket there are geogrids of square, rectangular and triangular (hexagonal) shape. Frequent coprehensive, independent studies have not confired the superiority of the triangular shape over the square. Introduction of patented geogrids with hexagonal apertures was purely a arketing ove intended to reduce copetition fro other geogrids. Does the ribs shape (cross section) ake a difference? Yes, it does. Polgrid geogrids have a specially designed shape of ribs fored on the basis of a concave rectangle and sharp edges. With this construction, geogrids interlock well with the aggregate and block the grains in the grid openings. This high cross-section, which has the proper thickness, is uch ore efficient in operation than the rib flat or rounded one. Is the node's efficiency iportant? It is very iportant. Efficiency (stiffness) of nodes is a easure of the node s strength copared to the strength of the ribs, as a percentage. This is extreely iportant, because the grains of the soil, working together with the geogrid, transit external loads to the lateral and longitudinal ribs. The rigid node enables the whole geogrid to function efficiently, effectively preventing the oveent of grains aggregate in the structure, creating a sei-rigid plate. How should geogrids be joined? Connections between the bands of geogrid both longitudinal and transverse, should be installed with overlap in width dependent on the ground conditions. In case of ground surface in the G and G3 group and the layer of aggregate of up to 30 c, the overlap should be at least 0 c; for ground surface in the G capacity standard and the layer of aggregate exceeding 30 c, the overlap should be at least c. Where necessary, the geogrid can be cut with knife, scissors, shears or saw. Can the Pietrucha Group help in selecting the best geogrid type for the specific project? Of course. Our copany provides technical support in choosing the appropriate type of geogrid and deterining the thickness of the layer of aggregate as well as the nuber of layers of geosynthetics for a particular project. The Pietrucha Group offers coprehensive assistance in other atters related to geosynthetics

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