» عنوان : Overview of Geosynthetic Materials, Their Characteristics, Applications, and Design Considerations
زبان : انگلیسی
تعداد صفحات : ۹۸
Outline of Presentation
- Geosynthetic Products
- Primary Functions
- Material Characteristics
- Design Considerations
Brief information about Geosynthetics :
Geosynthetics are synthetic products used to stabilize terrain. They are generally polymeric products used to solve civil engineering problems. This includes eight main product categories: geotextiles, geogrids, geonets, geomembranes, geosynthetic clay liners, geofoam, geocells and geocomposites. The polymeric nature of the products makes them suitable for use in the ground where high levels of durability are required. They can also be used in exposed applications. Geosynthetics are available in a wide range of forms and materials. These products have a wide range of applications and are currently used in many civil, geotechnical, transportation, geoenvironmental, hydraulic, and private development applications including roads, airfields, railroads, embankments, retaining structures, reservoirs, canals, dams, erosion control, sediment control, landfill liners, landfill covers, mining, aquaculture and agriculture.
Inclusions of different sorts mixed with soil have been used for thousands of years. They were used in roadway construction in Roman days to stabilize roadways and their edges. These early attempts were made of natural fibres, fabrics or vegetation mixed with soil to improve road quality, particularly when roads were built on unstable soil. They were also used to build steep slopes as with several pyramids in Egypt and walls as well. A fundamental problem with using natural materials (wood, cotton, etc.) in a buried environment is the biodegradation that occurs from microorganisms in the soil. With the advent of polymers in the middle of the 20th century a much more stable material became available. When properly formulated, lifetimes of centuries can be predicted even for harsh environmental conditions.
Early papers on geosynthetics (as we know them today) in the 1960s documented their use as filters in the United States and as reinforcement in Europe. A 1977 conference in Paris brought together many of the early manufacturers and practitioners. The International Geosynthetics Society (IGS) founded in 1982 has subsequently organized a worldwide conference every four years and its numerous chapters have additional conferences. Presently, separate geosynthetic institutes, trade-groups, and standards-setting groups are active. Approximately twenty universities teach stand-alone courses on geosynthetics and almost all include the subject in geotechnical, geo environmental, and hydraulic engineering courses. Geosynthetics are available worldwide and the activity is robust and steadily growing.