Application of geosynthetic materials in road construction. Road geogrid - types and purpose Functions of geosynthetic materials
Hundreds of thousands of kilometers of highways are laid and repaired every year. New construction, as a rule, is carried out taking into account modern loads and using new technologies, but the repair of the existing road surface, the so-called patching, is often carried out using outdated, unproductive methods.
The end result is of low quality. Road geogrid is a modern material with a cellular structure used in road repairs. Technologies involving the use of this material are distinguished by the high quality of work performed.
Application of geogrid road
The construction of new and repair of existing ones for various purposes is the main industry where road geogrid is used. Laying, depending on the technology, can be carried out in all layers road surface. Main purposes of road geogrid:
- Reinforcement of areas during repairs. The geogrid is laid over the damaged area of asphalt, and a new coating is placed on top of it. The structural properties of the mesh prevent the new coating from coming into contact with the cracks of the old one. In this case, the interlayer takes on most of the horizontal stresses.
- In places heaviest loads Dents and ruts may form on the road surface. During repairs, the geogrid is laid in recesses on top of the backfilled asphalt concrete. This allows you to distribute the load evenly over the entire area, preventing the formation of new dents.
- Geogrid is laid in a road surface when combining different types of coatings (for example, asphalt and cement-concrete) to prevent cracking.
- Strengthening joints between concrete slabs. When applied to a base of concrete slabs, weak spots are formed at the joints, onto which road geogrid is laid to reinforce the road surface.
- When the road is widened, cracks may form at the junction of the existing and new pavement. To prevent this, the joint is reinforced with geogrid.
- Modern technologies often provide for preliminary soil reinforcement. Road geogrid is also used for this. The use of a reinforcing layer in the construction of highways is an integral part of the technological process.
Types of geogrids and their properties
The type of geogrid determines its application. In addition to the material and cell size, the material is distinguished by the method of formation: biaxial (double orientation) and uniaxial (mono-oriented). Biaxial products with rectangular cells are designed for road construction, including on soft soils. Double orientation geogrids distribute loads well, which helps to increase service life. Uniaxial layers of cells elongated shape have high tensile strength, excellent for strengthening soils, landslide areas and embankments.
Products for asphalt concrete reinforcement
Road geogrid for asphalt concrete reinforcement allows you to distribute local external loads throughout the entire volume of the adjacent road surface. This material is used to extend the life of highways with concrete base, which are becoming more and more every year. This mesh also distributes internal stresses resulting from shrinkage of gradually hardening concrete.
Metal mesh is short-lived and expensive. Fiberglass and polymer geogrids are a cheaper alternative to metal reinforcement and at the same time have all the necessary characteristics:
- The material of such products is chemically inert and is not affected by temperature changes and the alkaline environment of concrete.
- Has a unique ability to distribute local loads.
- Has a light weight long term services, simple installation and affordable cost.
To improve performance, the base used in road construction, processed with bitumen.
Geogrid for road construction
The road surface is daily exposed to loads from traffic flows, which inevitably leads to its destruction and the formation of holes, potholes and cracks. The main reason for this is insufficient preparation of the base. Geogrid pavement allows you to increase the strength characteristics of asphalt concrete pavement, tensile strength and optimize the perception of horizontal stresses.
The use of such materials both in the construction of new roads and in the repair of existing ones can significantly improve performance characteristics and increase the service life of the coating. The use of geogrids for road construction in combination with geotextiles makes it possible to reduce the required volume of non-metallic materials during road construction. bulk materials, which will significantly reduce the cost of the project without changing the quality of the design.
Polymer geogrids
Road geogrid made from s is manufactured using thread knitting and piercing technology. This allows you to maintain the original high strength of the material. The structure of the geogrid is fixed cells of a size that is larger than the material they are filled with. Thanks to this, the backfill interacts with the base (soil, rock, other base materials used in construction).
They are used as a reinforcing layer in the lower layers of the road base. The use of polymer meshes in road structures makes it possible to strengthen the road base and prevent the interpenetration of materials from different contacting layers. Strengthening is achieved by limiting the movement of granules of bulk base material outside the cell. The formed composite layer (geogrid + granular material) has increased resistance to dynamic loads.
Fiberglass products
Geogrids based on fiberglass are used as reinforcing elements and protective and separating layers in the construction and repair of federal and regional highways, airfields, bridges and overpasses. Use of fiberglass mesh for reinforcement asphalt concrete pavements allows you to increase the operating time between repairs by 2-3 times. Road maintenance costs in regions where fiberglass geogrids are actively used are reduced by 40%. Such materials have high technical and physical properties: resistance to aggressive environments, the ability to withstand high transverse and longitudinal loads. Fiberglass geogrids significantly improve the strength and mechanical characteristics of reinforced elements.
Production
Today the following main types of geogrids are produced:
- extruded polymer;
- glued fiberglass;
- stitched mesh made of polyester threads and fiberglass.
Modern technologies and equipment with a wide variety of production methods make it possible to produce geogrids with different properties, from different raw materials and with different fastenings in the nodes. The main requirements are:
- resistance to natural factors;
- resistance to aggressive environments under operating conditions;
- UV resistance;
- resistance to stains;
- strength and stability of properties.
Material selection
From the variety of types of geogrids and their standard sizes, the choice should be based on the purpose, the method of forming the cells and the type of raw material. Interlayers are intended for reinforcement, separation of layers, erosion control, and leveling of soils and foundations. Having decided on the purpose, you need to select a specific type of geogrid and its standard size. Depending on the properties of the raw material, the characteristics of the material are selected, which can be resistant to hydro-, bio-, thermal and chemical influences.
Geogrid has become widespread in the strengthening of slopes. The material is used for reinforcing surfaces in road construction or landscape design. To fill it, sand, soil, crushed stone and gravel are used. When carried out correctly, the meshes fully cope with the assigned tasks and have a long service life. The Resurs company carries out wholesale supply of such materials at the most favorable prices, providing several effective solutions to choose from.
Characteristics of geogrid for strengthening slopes
The product is roll material, which consists of geothreads woven together in a special way. Volume cells reliably hold any filler, regardless of the slope level. This mesh helps to distribute loads evenly over the entire base area. In addition to its reinforcing function, the material protects soils from erosion, significantly improves the drainage system, and prevents the leaching of particles under the influence of precipitation and melt water.
Geogrid is used to strengthen slopes when laying roads and reinforcing slopes. In the first case, it provides reliable strengthening of the canvas, which is achieved thanks to adhesion various materials. The material has standard sizes 2x5 or 4x5 m.
Advantageous characteristics and features of geogrid
The wide demand for this material is due to its large number of operational advantages. These include:
- long service life reaching 25 years;
- wide temperature range of application, ranging from -70 to 70 degrees;
- chemical inertness, easy to tolerate negative impact alkalis, acids and other substances that have a destructive effect;
- simplicity and high speed installation without the use of expensive equipment;
- resistance to direct sunlight;
- unattractive to insects, birds and rodents;
- ability to withstand uneven shrinkage and soil mobility;
- and reducing harmful emissions.
The use of geogrid allows you to reduce costs for other construction work. Thanks to it, the thickness of the inert filler is reduced by 50%. Universal characteristics help solve problems of any complexity, including in harsh climates.
Modern requirements and standards road surface become achievable through the use innovative materials, which, in addition to their unique properties, will help save on the construction process and possible repair work in the future.
In addition, modern geosynthetics convenient to transport, unlike its competitors - bulk materials for drainage. Their low delivery costs make them even more attractive to road builders.
Application of geotextiles in road construction
Road geotextiles It is important to use it to build an overpass or bridge when peat, clay or waterlogged soil is added to the base of the canvas. This is done in order to differentiate layers of different fractions (crushed stone, sand, soil) and prevent their mixing, which entails deformation of the road surface.
Geotextiles have high strength. This allows it to be used more than once, but even after operation and further dismantling of a temporary road.
Geotextiles vary in density. For road construction, materials are used from 250 g/sq.m for medium-load roads and car parking lots to 600 g/sq.m for roads especially loaded with heavy vehicles, runways, and so on.
The excellent performance characteristics of road geotextiles allow it to find everything great options applications in the construction of all types of roads. This material is characterized by elasticity, resistance to various mechanical and chemical damage, resistance to temperature changes and excellent water-permeability qualities.
Also, road geotextiles are used as a restorer of the road surface with its further reinforcement after the work has been carried out. renovation work overpasses and highways. By preventing fractions of different materials from mixing, this geosynthetic evenly redistributes loads, which eliminates the possibility of failure and deformation of the coating under heavy vehicles.
The GeoSM company is a manufacturer of geotextiles. In order to buy road geotextiles at a wholesale price without markups from intermediaries, call us at 8-800-500-32-24. Our managers will help you select the required density of this geosynthetic material, based on the conditions of its use and the required functionality.
Application of geogrids in road construction
Geogrid is a rolled polymer geomaterial with a mesh structure.
Geogrid is a highly effective building material with high strength, wear resistance and excellent adhesion (adhesion of surfaces of different fractions).
Functions of a road geogrid
Geogrid is used as a separating and reinforcing layer in the construction and repair of roads different levels: federal, local, embankments for railway tracks, as well as sidewalks and areas for various purposes.
The use of geogrids in road construction helps to strengthen the top layer of the road, making you forget about cracks, ruts, holes and other defects in asphalt and cement concrete. Geogrids prevent dirt roads from crumbling and are also used when applying new asphalt to old ones. concrete covering roads and reinforces seams during its repair.
Classification of road geogrid
The classification of road geogrids is quite simple.
The geogrid has:
- scope of application (for asphalt concrete or soil);
- material (fiberglass, polyamide, polyester, polypropylene, polyester);
- design (uniaxial - mono-oriented, biaxial - double-oriented).
Advantages of road construction technologies using geogrids
Road construction using geogrids has a number of advantages:
- significant reduction in construction time for facilities;
- minimal costs;
- reduction (up to 40%!!!) consumption of bulk materials (sand and crushed stone);
- reducing the likelihood of road repair frequency;
- improving the transport and operational characteristics of the road surface;
- increasing the service life of roads.
The GeoSM company is a manufacturer of geogrids. In order to
buy road geogrid at a wholesale price without markups from intermediaries, call us at 8-800-500-32-2 4. Our managers will help you choose the required type of geosynthetic material, based on the conditions of its use and the required functionality.
Application of geogrids in road construction
Geogrids are increasingly used in road repair and construction work that passes through wetlands, sandy granular soils and permafrost zones.
Flat geogrids are actively used in the construction of roads consisting of many lanes. This material is located between the load-bearing base and the bedding layer.
Its use speeds up road construction and makes it economically profitable.
The GeoSM company is a manufacturer of geogrids. In order to buy road geogrid at a wholesale price without markups from intermediaries, call us at 8-800-500-32-24. Our managers will help you select the required type of geosynthetic material, based on the conditions of its use and the required functionality.
Application of geomembranes in road construction
Geomembranes is another geosynthetic material that is successfully used in road construction and repair. The main raw material for its production is polyethylene high density.
Geomembranes in road construction perform two main functions:
- waterproof the lower layers of road pavement, raising moisture to the top;
- reinforce the road surface from possible deformations.
Advantages of geomembrane in road construction
Application of geomembrane:
- reduces the volume of use of bulk materials for the base of the road surface by almost 50% - reduces the cost construction work;
- increases the strength of the road surface, making it more durable and reliable - increases the repair-free period of the road;
— practically eliminates the possibility of siltation of the layers underlying the road surface;
— protects layers of road pavement from destructive effects groundwater;
— reduces and distributes the pressure exerted on the road when the ground freezes.
The GeoSM company is a manufacturer of geomembranes. In order to buy a road geomembrane at a wholesale price without markups from intermediaries, call us at 8-800-500-32-24. Our managers will help you select the required density of this geosynthetic material, based on the conditions of its use and the required functionality.
Buy geosynthetics
The GeoSM company produces and sells geosynthetic materials used for road construction.
In order to buy geosynthetics at wholesale prices without markups from intermediaries, call 8-800-500-32-24 and order high-quality geomaterials for road construction right now!
n1.docx
FEDERAL EDUCATION AGENCY
Federal state budget educational institution
higher professional education
"TYUMEN STATE OIL AND GAS UNIVERSITY"
INSTITUTE OF TRANSPORT
Department: "TTS"
on the topic: “Use of geo synthetic materials in road construction"
Completed: art. gr. MSO-07-1
Mikurov I.S.
Checked by: Yarkin A.V.
Tyumen 2011
Introduction
Geosynthetic materials have become quite widespread in the strengthening of highways; otherwise it is called: “Reinforcement of highways.”
The scope of geosynthetics is very wide, and their use is effective. Geosynthetic materials have been used in Europe for several decades, having practically revolutionized road, civil and special construction. Economic efficiency and wide range of application of geosynthetics, incl. in areas where they are practically irreplaceable, we can talk about them as very promising materials.
The use of geosynthetics in road construction already has its own history, although not a very long one. Geosynthetics in the form of geotextiles have been used abroad since the late 60s.
The production of these materials in the world has developed rapidly, and is currently offered on the world market a large number of various types geotextiles, geogrids, geogrids and geocells, geothreads, as well as geoplates used as thermal insulators. They all differ in their purpose, the composition of the feedstock, production technology, polymer consumption, physical and mechanical characteristics, width of the webs, etc. In particular, geotextiles (non-woven fabrics using a needle-punched or adhesive production method) are made from synthetic fibers: polyester (lavsan), polypropylene, polyamide (nylon); geogrids - made of polyester or polypropylene threads of increased strength, glass rovings; geoplates - based on polystyrene.
1. History of the development of the use of geosynthetic materials in the Russian Federation
The Russian experience in using geosynthetics began in the mid-70s, first with the purchase of these materials abroad, in particular in Hungary and Czechoslovakia, then with intensive scientific research in industry research institutes and the own developments of manufacturing enterprises. Currently, approximately 380 different types of geosynthetic materials are produced in the world. The use of geosynthetics is envisaged in projects of more than 100 thousand various structures every year all over the world.
The reasons for this are based on two main factors: economic - the use of geosynthetic materials can significantly reduce capital investments in the construction, repair and maintenance of highways; environmental - the use of geosynthetic materials is beneficial for environment(consumption decreases natural materials, the volume of preparatory geotechnical work is reduced, etc.).
Additionally, the use of geosynthetics allows:
increase the durability of subgrade structures and road pavements;
improve the quality of work;
reduce the amount of rework (additional work);
improve production standards.
And finally, the conditions market economy and economic independence force builders to count money. For example, the use of geogrids made from glass roving to reinforce asphalt concrete makes it possible to reduce the thickness of the latter by up to 20%.
2. Geosynthetics
Geosynthetics (geosynthetics) are a group of synthetic materials that are widely used in road and civil construction; the use of geosynthetics opens up new opportunities for solving a variety of problems in the design and construction of roads, as well as complex engineering structures.
Geosynthetics are polymer materials, designed to change the natural properties of soils. The change, as a rule, concerns the filtration properties of the soil (usually the filtration coefficient of too loose soil is reduced), or its strength characteristics (for example, the strength of weak soils is increased using geogrid reinforcement).
Specialists from the geosynthetics department of the Euroizol company offer the following definition of these materials: “Geosynthetics is a material in which at least one of the components is made of a synthetic or natural polymer in the form of a canvas, tape or three-dimensional structure, which is used in contact with the soil and other construction materials. materials. The combination of soil with GS should be considered as the formation of a new one. composite material, which combines the functions of both soil and synthetic material."
The qualitative and chemical-physical characteristics of geosynthetics are determined by the properties of the polymers used for their production. Thus, qualities such as water and frost resistance, corrosion resistance, low weight, high tensile strength are the “merit” of polymers. At the same time, disadvantages polymers (rapid aging under the influence of UV radiation, loss of strength at a temperature of + 80 -120°C, flammability) are leveled out by the specific application of GS. Materials are used in structures, the vast majority of the volume of which is soil or bulk rocks, protecting polymers from light and temperature influences.
Geotextiles are considered the progenitor of geosynthetic materials. The same foreign standards were originally created for these materials.
Depending on the area of application in soil structures, geosynthetics in general can perform the following functions:
reinforcement to improve the shear resistance of granular materials;
separation, to maintain the structural integrity of the granular layers;
filtration, for the passage of liquid and retention of soil particles;
drainage for collecting and draining liquid outside the structure;
Erosion control, when preventing soil erosion due to water or wind;
protection, to prevent damage to the structural layer, for example, insulation around artificial structures in the subgrade when they are backfilled;
insulation to prevent migration of liquids and gases.
The first biaxial geogrid was produced in the 1980s by extruding a web of polyethylene or polypropylene, perforated after stretching with a regular network of patterned holes. Such extruded and oriented geogrids are called inelastic (rigid) geogrids. Biaxial geogrids are widely used in the construction of roads, airfields, container sites, parking lots, etc. on weak and heterogeneous soils.
The basic principle of operation of biaxial geogrids is to eliminate the interpenetration of structural layers and fix the filler due to the wedging of its particles in the geogrid cells. When filling and compacting geogrid cells with inert material, particles of the material are fixed in the cells, and a “mechanical stabilization” effect is created. Biaxial geogrid has high rigidity, which allows it to withstand high loads at low deformations.
Rice. 2.1. Biaxial geogrid
Advantages of use:
increasing the bearing capacity of the base of the fortified area;
separation of non-cohesive layers, protection against penetration of coarse-grained material into the lower layers;
reduction of deformations due to frost heaving;
allows you not to increase the thickness of the ballast prism on soft soils;
reduction in the rate of foundation settlement;
increasing the speed limit (railway base).
SSNP geogrids are geosynthetics made from impregnated thread-stitched glass meshes. They are used in the construction or repair of hard road pavements with asphalt concrete pavement. The use of geogrids in road construction allows us to solve a number of existing problems.
Geogrids SSP - Neftegaz geosynthetics designed for reinforcement, stabilization of soft soils, construction of temporary roads, ensuring local stability of slopes and slopes.
Rice. 2.2. Geogrid
Glass geogrid brand SSNP-34BT produced by JSC STEKLONiT (Ufa) is a mesh of two layers of roving, fastened together with a stitching thread and impregnated with a binder to increase strength and adhesion to asphalt concrete. Let us consider the mechanism of interaction between the SSNP grade geogrid and the asphalt concrete layer. Asphalt concrete is ideal material for the construction of non-rigid type coatings, since due to the high viscosity of the asphalt binder and the roughness of the filler grains, it has high resistance to short-term loads.
Tests of samples - beams made of two-layer asphalt concrete (top layer 3 cm thick, bottom layer- 4.5 cm), reinforced with a road mesh located between layers of asphalt concrete, and control - unreinforced - showed that reinforcing asphalt concrete with SSNP mesh slightly increases the ultimate force and relative bending deformation. However, it was also revealed that the destruction of asphalt concrete samples with a road grid requires 2.85 times more energy costs, and, consequently, the rate of crack formation in asphalt concrete slows down by the same amount. Thus, the SSNP mesh increases the elastic properties of asphalt concrete, increases its distribution capacity, as a result of which the stresses from the car wheels are distributed over large area, which helps to reduce stress concentration and, therefore, slows down the process of crack formation. In addition, the mesh increases the resistance to tearing of the road surface by ice, which is important for regions with harsh climatic conditions.
In terms of their operational characteristics, the road nets of OJSC "STEKLONiT" are not inferior to the corresponding foreign materials and can significantly increase the transport and operational performance of coatings, increase the time between repairs, and in general free up material resources for other types of work and objects. SSNP grids have proven their exceptional qualities in a number of projects. Fiberglass meshes of JSC STEKLONiT were used when laying roads in St. Petersburg, Moscow, Astana, and during the reconstruction of airports in Nizhnevartovsk and Khanty-Mansiysk.
Geotextile high-strength stabilex
Geotextile Stabitex (geofabric) - belongs to the section of geosynthetics and is a woven fabric made of high-strength polyamide threads. It is used for the construction of embankments of increased steepness from bulk materials for the construction of retaining walls; protection of territories from landslide phenomena; separation of soil layers; strengthening the foundations of railways and highways, stabilizing soft soils. High-strength geotextile Stabitek is an analogue the following materials: geolon (geolon), polyfelt (polyfelt), taipar (typar), cortex (kortex).
Rice. 2.3. Geotextile (geotextile)
Geotextiles (dornit)
Geotextile (dornit) – geosynthetic material is a needle-punched or spunbond non-woven fabric made from polyester fibers. Excellent physical and mechanical characteristics of Dornit geotextiles, as well as the widespread use of it in the most different areas, allow us to assert that Dornit geotextiles are the leader among geosynthetics in terms of the range of applications both in construction and in everyday life.
Rice. 2.4. Geotextiles (dornit)
Application of geotextile dornite:
geotextiles are used as a separating layer (filter) between the soil and aggregate (sand, crushed stone, etc.);
prevents the penetration of soil particles into drainage systems(drainage of basements, flat roofs);
during the construction of tunnels, geotextiles protect the insulating coating from damage, form a drainage layer, and carry ground and storm water to the drain;
dornite geotextile acts as a filter under the coastal fortification;
High-density geotextiles can be used as a reinforcing layer on weak-bearing soils;
used to strengthen the bottom of settling tanks treatment facilities, simultaneously acting as a filter, replacing the layer of sand;
used as heat and sound insulation;
when laying pipelines as ballast.
One of the promising structures for volumetric soil reinforcement is the geotechnical grid (geogrid). Geogrid is a geosynthetic material that is a flexible compact module consisting of interconnected plastic tapes, forming in an extended position a spatial cellular structure with given geometric combinations and dimensions. Geogrids are resistant to ultraviolet radiation, fresh and salt water, chemical exposure soil and aggressive environments. And most importantly, the material is durable, non-toxic and environmentally friendly. The combination of these factors determines the technological effect of using geogrids.
Wide application is due to high physical and mechanical properties: strength, low material consumption to the effects of weather, climatic and hydrogeological factors, durability and environmental safety.
Depending on the construction conditions, reinforcement using geogrids can be either single-layer with a horizontal layer of geotextile, or multi-layer, ensuring uniform reinforcement of the entire massif of the earthen embankment.
Rice. 2.5. Geogrid volumetric
Application of geogrids:
strengthening slopes and slopes, increasing the overall stability of slopes;
railway construction. Strengthening the ballast prism;
development construction sites with minimal costs;
strengthening pipeline protective structures;
the use of geogrid makes it possible to use local materials during construction;
reduction of direct costs by replacing traditional load-bearing, protective and insulating types of reinforcement by up to 20% of their cost;
during the construction of airfields.
Rice. 2.6. Geogrid volumetric
Geomembrane
HDPE geomembrane is a rolled waterproofing geosynthetic material made from high-density polyethylene. Reliably protecting, ensuring waterproofing and absence of dampness in buildings is one of the main tasks of modern construction design. Those who understand how important it is to ensure the reliability and safety of buildings and structures are no longer satisfied with the currently existing waterproofing systems; That's why the HDPE geomembrane was developed.
The geomembrane is characterized by high strength and resistance to various substances; This is a product that, thanks to its numerous protrusions, allows the surfaces to be protected to be ventilated and moisture to be removed from them.
Applications of HDPE geomembranes:
waterproofing and strengthening of slopes;
during the construction of reservoirs and irrigation canals;
protection of the outside of the walls;
protection of retaining walls;
replacement of lean concrete (pillars under the foundation);
ventilation and drainage of internal walls;
ventilation and restoration of old premises (protection inside walls);
protection and double waterproofing;
drainage, waterproofing and root protection;
strengthening, thinning and insulation;
waterproofing and erosion protection;
waterproofing and load distribution (during tunnel construction).
Rice. 2.7. Geomembrane
3. Geosynthetic materials in road construction
The intensification of road construction, as operators of the geosynthetics market hope, will have a positive effect on sales volumes of these materials. Firstly, this segment is one of the main consumers of geosynthetics. Secondly, domestic road construction enterprises are increasingly turning to the use of more modern materials and technologies, which, of course, include geosynthetics.
In this segment, geosynthetic materials are used to construct slopes of increased steepness, retaining walls, and strengthen the bases of road embankments. In addition, geosynthetics are used to protect overpass cones, reinforce asphalt pavements, and separate structural layers of road “pies,” as elements of drainage systems.
In road construction they are mainly used Various types geotextiles, both woven and non-woven. In this case, they are taken into account more or less pronounced characteristics- mechanical, filtering.
In addition to geotextiles, geogrids are widely used to strengthen (reinforce) slopes or road surfaces. The use of geogrids allows for significant savings building materials: for example, reinforcing a layer of crushed stone in a road construction system “gives” 60-70% savings on the same crushed stone.
The use of geosynthetics is economically more effective than traditional technologies such as the construction of concrete retaining walls and soil replacement during construction on weak foundations. In railway construction, geosynthetics are mainly used for reinforcing railway tracks and embankments (geotextiles, geogrids).
Moreover, it is almost impossible today to carry out high-quality construction of runways and bridges without geosynthetics that meets all requirements, as experts note. Often these objects are built on weak soils, and therefore require reliable and durable reinforcement.
4. Application of geosynthetic materials
When constructing roads (from pedestrian to railway) and parking lots, crushed stone is usually used. But over time, ruts form on the road on a weak foundation (clay, peat or waterlogged soils), or the crushed stone generally “sinks.” Geotextiles help solve these problems by preventing the crushed stone backfill from mixing with the base and maintaining the original thickness of the backfill, which, in combination with the significant elastic modulus of the geotextile itself, allows:
significantly increase bearing capacity such a design;
ensure an increased degree of compaction during the construction phase, preventing crushed stone from being pressed into the soft substructure;
reduce road damage caused by frost. Trapped tiny particles (fine inclusions) act like a sponge, absorbing water and expanding when frozen;
prevent rutting.
reduction in installation costs (reducing the use of crushed stone to achieve the same load-bearing capacity);
reduction of construction time due to faster and better compaction;
cost reduction Maintenance and increasing the service life of the structure.
Geotextiles are also widely used in the construction of paths and platforms from paving slabs. Soft (without concrete screed) laying paving slabs is much lower in price (the difference in the cost of concrete and reinforcement and work reaches 70%), it prevents sand from being washed out, mixing it with crushed stone or soil base, increases the rigidity of the structure and significantly reduces the likelihood of subsidence. You get excellent results, the opportunity easy repair and redevelopment with significantly lower material, labor and time costs.
Embankment reinforcement
Rice. 4.1. Reinforcement scheme
Used to reinforce fine-grained, cohesive soil.
Prevents slope collapse.
Reduces increased pore pressure of the soil.
Firstly, their use makes it possible to optimize economic costs and ensure high quality construction work on reinforcement and waterproofing of structures and structures, the basis of which is loose rocks - soil, sand, gravel mixtures and so on.
In global construction practice, geosynthetic materials have made significant changes in many aspects of transportation and civil engineering practice in less than 30 years. If in the 70s of the 20th century there were only 5-6 hydrocarbons on the world market, then in 2000 their number was about 600. The volume of use is 1 trillion square meters. m per year for a total amount of about 1.5 billion USD. Such growth rates and volumes indicate the extremely wide application and effectiveness of HS in construction due to their properties and functions in structures. In many cases, the use of GS can significantly increase safety margins, durability and reliability, improve performance and reduce cost compared to traditional design solutions.
Thus, according to experts in the field of geosynthetics, the use of geosynthetics in road construction, for example, geotextiles to combat “reflected cracks” Polyfelt PGM 14 and PGM G (repair of asphalt concrete pavements of highways) reduces stresses in areas of old cracks by up to 40% due to the absorption of deformations between the old and new coating. And the overall effect of the use of these materials is a significant slowdown in crack formation, a threefold increase in the time between repairs, savings on road operation, regular routine and extensive repairs and reinforcement of the pavement. Secondly, the area of effective use of geosynthetics is not just wide. The materials work great where the use of other solutions does not provide such a reliable and durable result. Domestic construction production, unlike the Western one, directly from the perspective wide application People began to “consider” geosynthetic materials relatively recently, and the list of problems associated with the use of this material is quite standard. There is no official Ukrainian classification of these materials, which stems from a completely traditional situation - the lack of standards. And awareness of the properties and advantages of GS customers still leaves much to be desired.
Conclusion
The use of geosynthetic materials in road construction makes it cheaper and makes it much stronger. The use of geosynthetics is economically more effective than traditional technologies such as the construction of concrete retaining walls and soil replacement during construction on weak foundations. The use of geotextiles significantly increases the bearing capacity of the road; provides an increased degree of compaction during the construction phase; reduces road destruction caused by frost; prevents rutting.
With the use of geosynthetic materials, the cost of maintenance is reduced and the service life of the structure is increased.
Geosynthetic materials are used in all branches of construction. These are the materials of the future. Their development must increase.
Their use improves both the construction itself and its operation. The service life of structures using geosynthetic materials increases. We need to use more geosynthetics.
Bibliography
1. SNiP 2.05.02-85. Highways/Gosstroy USSR.-M.: CITP Gosstroy USSR, 1986.
2. Educational and methodological manual to the implementation of abstracts on the disciplines "Engineering Geology" and "Engineering and Construction Karstology" / ed. Mulyukova E.I. USNTU, 2009. 29 p.
Road geogrid is one of the most popular materials in the world. construction market, which is a geosynthetic fabric with a pronounced mesh structure. The cellular structure is formed from strong threads, fastened at the knots with stitching thread, by weaving, gluing and other methods. Geogrid is supplied in rolls. It is made from different polymers with varied technical capabilities.
Road geogrids are used not only on soil surfaces, but also when reinforcing asphalt concrete. The main area of application of geogrids is road construction. This material allows you to significantly increase the performance characteristics of the road surface. The use of geogrids is especially important in the construction of runways, since they are subject to increased load.
Performance characteristics
The road geogrid is being processed special composition, which increases the physical and mechanical characteristics, thanks to which it is characterized by the following positive properties:
- Impeccable strength and good resistance to deformation;
- Road geogrid is resistant to environmental influences, that is, it does not collapse when high humidity, when exposed to ultraviolet rays and does not rot;
- The service life of a road geogrid is half a century or more.
Types of road geogrids
Road geogrid is made from various polymer materials:
- polyester;
- polyamide;
- polypropylene;
- polyethylene;
- fiberglass;
- polyester
Properties and specifications road geogrid directly depend on the type of raw material used as a base. For example, polypropylene geogrid has high technical characteristics, but does not withstand exposure to ultraviolet rays. And geogrids made of polyester are characterized by poor resistance to chemically aggressive components. Polyamide-based meshes lose their strength at high humidity.
Depending on the cell formation technology, there are two types of geogrids: single and double orientation. That is, the choice of geogrid depends on the conditions of the project, and the consumer can choose the material, taking into account the tasks that he needs to perform.
