Application and development of geotextiles

Geotextile usually refers to the textile used in civil engineering it has good chemical and physical properties and hydraulic properties pan applied to a variety of civil engineering projects such as barrages, dams and highways and other projects. Geotextile in civil engineering plays a very important role in the following about the application and development of geotextile is introduced.

1 geotextile type and function

1.1 types and characteristics of geotextile

Geotextile is broadly divided into four types, namely, woven, non-woven, synthetic and composite.

Woven type is manufactured using traditional textile technology according to its processing methods can be subdivided into woven, woven and knitted.

Non-woven type is commonly known as "nonwoven" according to its bonding method can be subdivided into needle-punching type, chemical bonding type and hot melt type and so on.

Synthetic can be subdivided into geomembranes, grids, meshes, wadding sheets and geosynthetics boards according to product classification. Composite type refers to the use of two or more than two materials by different methods of composite products such as composite geomembranes, drainage boards and geotechnical pads and so on. The above four types of non-woven geotextile price is lower, but the tensile strength and initial modulus are less than woven geotextile for high tensile strength requirements for the general use of woven geotextile. Although the aperture size and porosity of woven Geotextiles can be controlled in production, but the organization of the intertwined points are not linked to the mechanical force is easy to make the fibers or yarn wandering aperture or even local breakage, fiber breakage caused by yarn bloom, fall off. The non-woven geotextile in addition to a high tensile strength, its deformation modulus, pore size and other indicators can be adjusted as needed. Of course, synthetic and composite geotextile is high-tech content, high value-added products with non-woven and woven geotextile advantages of both is today's domestic and foreign vigorously promoted geotextile.

1.2 Function and life of geotextile

Geotextile is a multi-functional product in engineering applications have six main functions. Different types of geotextile in the actual application of a function is often the main other functions as a supplement.

(1) Filter layer function

Geotextile has good water permeability, air permeability can effectively retain soil particles, fine sand and small stones and filter the water flow to prevent soil damage to maintain the stability of soil and stone works.

(2) Drainage function

Non-woven geotextile is a good water-conducting material which can be used to form a drainage channel inside the soil body to drain the excess water inside the soil structure is now widely used in earth dams, road retaining walls and soft soil foundation drainage.

(3) Isolation function

Geotextile isolation of different building materials, such as soil and sand, sand and gravel, soil and concrete, etc. can make two or more kinds of materials do not mix, do not lose, to maintain the overall structure and function of the material, so that the structure by the load capacity to strengthen. Utilizing the isolation function of geotextile, it can be widely used in railroad and highway roadbed, airport runway, earth and stone dam project, river training and construction of weak foundation treatment and so on.

(4) Reinforcement function

Geotextile buried in the soil, can effectively improve the overall stress conditions of the soil, enhance the tensile strength of the soil and deformation resistance, improve the stability of the building structure. It can be applied to earth and stone structure dams, steep slopes, retaining walls, slope stabilization, weak foundation treatment and so on.

(5) Protective function

Geotextile can effectively diffuse, transfer or decompose the concentrated stress to prevent the soil body from being damaged by external force. It is mainly used in bank protection, bottom protection project, road slope protection, river organization, coastal tide prevention and so on.

(6) Seepage control function

The use of geomembrane or composite waterproof material can effectively prevent the seepage of water or other liquids, to protect the environment and the safety and stability of construction projects. At present, geomembrane and its composite materials have been widely used in embankments, dams and reservoirs project to replace the clay heart wall, seepage-proof sloping wall, etc. At the same time, it provides a new choice of materials for swimming pools, housing construction, tunnels, underground construction and environmental engineering. Geotextile in the correct use of the conditions, life expectancy of up to 50 years to 100 years or more. Relevant experts pointed out that geotextile is considered effective when its strength is not less than 45% of the original strength. Experiments have proved that the domestic geotextile materials in the buried 10 years later, the strength can be maintained at more than 80%. According to information on foreign geotextile in the buried 20 years later, geotextile strength can be maintained at about 75%. Dutch scientists design and manufacture of geotextile materials service life target up to 200 years.

2 Domestic application of geotextile production prospects

At present, the general trend of the development of domestic geotextile is: products to the series, synthetic, composite direction, application to large and medium-sized project development. Corresponding theoretical research, testing technology, design standards, construction technology and other aspects are constantly improving and perfecting. At present, some of the larger cross-century domestic projects are applied to varying degrees of geosynthetics, so China is the application of geotextiles and sales of the largest market, generally by domestic and foreign manufacturers of concern. In the next few years, geotextile application prospects.

2.1 Water conservancy construction project

In recent years, the country's investment in water conservancy construction continues to increase, the implementation of the Yangtze River, the Yellow River, the Huaihe River, Taihu Lake Basin and other large rivers and rivers of long-term governance reform. Southeast coastal water conservancy projects and the vast agricultural water conservancy construction has also been carried out; now further proposed to the central and western development, improve the natural environment of the whole country.

Shanghai is China's geotextile sales over the years one of the largest market. With the development of the Pudong New Area, a large number of infrastructure projects have been carried out, geotextile consumption has increased year by year. "The Yangtze River estuary deep water channel improvement project is currently the largest domestic geotextile consumption of the project. It is expected that a project with composite geotextiles 14 million square meters, non-woven geotextiles 670,000 square meters, geomembrane bags 590,000 square meters, which does not include other aspects of the dosage, the amount of visible works is very considerable.

2.2 environmental engineering

Environmental engineering mainly includes solid, liquid, gas waste disposal and pollution prevention, etc., while expanding the green area, improve the ecological environment. Construction of landfill, geotextile is the best choice of material. In addition, the environmental greening using geotextile effect is excellent, especially three-dimensional green environment. Such as the construction of roof gardens, the use of composite geotextile is ideal, not only to prevent seepage does not make the roof leakage, but also available for plants to use water, the development of this project has great prospects for development.

3 Conclusion

Geotextile technology is a widely used mature technology, the development and application of broad prospects in China; at the same time, geotextile is a high-tech content, high value-added products, its application and promotion can drive the textile industry's industrial and product structure adjustment, the formation of the textile industry, a new point of economic growth, but also to drive and support the technological progress of the other sectors of the national economy, therefore, the relevant state departments and production, marketing enterprises should increase Geotextile application and promotion of publicity efforts for the healthy development of China's geotextile industry to create a favorable environment.