30-05-2012, 03:13 PM
GEOSYNTHETICS-THEIR APPLICATIONS IN CIVIL ENGINEERING
GEOSYNTHETICSTHEIR APPLICATIONS IN CIVIL ENGINEERING.doc (Size: 97 KB / Downloads: 172)
DEFINITION:
The term Geo means it refers to earth. The realization that the materials are almost exclusively from human made products gives second part of the name synthetics.
The materials used in manufacture of geosynthetics are primarily from the plastics industry i.e. they are primarily polymers although rubber, fiber glass and other materials are some times used.
FAMILIES OF GEOSYNTHETICS
Geotextiles: They are textiles in traditional sense, but consist of synthetic fiber rather than natural ones such as cotton, wool or silk. Thus bio degradation is not a problem. These synthetic fibers are made in to a flexible, porous fabric by standard weaving machinery or are matted together in a random.
Geosynthetics as a paving inter layer:
Pavements are civil engineering structures used for the purpose of operating wheeled vehicles safely and economically. Commonly a paved road becomes a candidate for maintenance when its surface shows significant cracks and potholes. These cracks and holes cause lot of problems. The cracks under the overlay rapidly propagate through, to the surface. This phenomenon is called reflective cracking, which is major draw back of asphalt overlays. Reflective cracking in asphalt overlay are basically a continuation of the discontinuities in the underlying damaged pavement. When an overlay is placed over the crack, the crack grows up to the new surface.
Geosynthetics as liners:
As a ground water pollution control mechanism, the use of a liner on the bottom and sides of a landfill has been considered necessary for many years. This necessity is created by the moisture in the landfill materials interacting with the contaminated wastes, forming a liquid called leachate. A liner that prevents rather than minimizes leachate migration provides added assurance that environmental contamination will not occur. Membrane liners (geomembranes) have more demand when compared to clay liners because it has following drawbacks.
CONCLUSIONS:
Geo textiles can be used as alternatives to stress relieving granular layers, seal coats, rubberized asphalts etc. for controlling surface moisture, infiltration and retarding reflection cracks in pavement overlays.
It is a best reinforcing materials for structures basing on soft material. It also acts as good drainage thereby controlling erosion.