Depth analysis of anti-filtration properties of geotextile
Number of hits：1072018-12-01 00:00:00
(1) Traditional programmes
The anti-filtration layer is made of sand, gravel, or pebbles of different sizes of 2-4 layers. The particles gradually increase in the direction of the water flow, and any layer of particles is not allowed to pass through the pores of the adjacent thicker layer. The same layer of particles can not produce relative movement.
Diagram of anti-filtration mechanism
1-Drainage water body; 2-geotextile; 3-`` Natural "anti-filtration layer; 4-Original soil
At present, its application has more mature experience. The characteristic of this plan is that particles of an adjacent layer of two layers should not pass through the pores of a larger layer, so that the diameter of each layer of soil material is strict and must be manually screened. The anti-filtration effect is good but the construction is complex and the cost is relatively large.
2 Non-woven geotextile programme
Geotextile as a new type of anti-filtration material has been widely used in water Conservancy projects in recent years, and it is becoming more mature. Compared with the traditional sand and gravel anti-filtration scheme, the geotextile non-woven scheme saves more than half of the material cost and can greatly shorten the duration and has a certain competitive advantage.
3 principle of action
The principle of using geotextile non-woven cloth instead of traditional grained materials as anti-filtration layer is the same, that is, they must meet the anti-filtration criteria, that is, geotextile non-woven cloth must have soil retention, permeability and blocking.
Soil retention means that protected soil particles can not be lost from the pores of non-woven fabrics.
The permeability should be greater than the permeability of the protected soil material to ensure smooth water flow.
The anti-blocking ability guarantees that the non-woven cloth will not be invalidated by fine earth particles.
4 geotextile anti-filtration properties
The main performance parameters that are closely related to the anti-filtration performance of non-woven geotextiles are equivalent aperture and permeability coefficient. Shandong Haoyang New Engineering Materials Co., Ltd. has advanced geotextile production process and stable performance index. The equivalent aperture can reach 0.05 ~ 0.2 mm, and the permeability factor can reach 1.0 ~ 9.9 ×(10-1 ~ 10-3) cm/s. And according to the needs of engineering design, the products with specific parameters can be developed.
In addition to the strict requirements of the above parameters, physical indicators such as the unit mass, thickness, tensile strength, tear strength, and porosity of geotextile also have a direct impact on the success or failure of the project.