What is the difference between short-filament geotextile and ordinary geotextile?

Regarding the difference between short-filament geotextile and ordinary geotextile, this article will conduct professional analysis from three dimensions: material properties, production process, and engineering performance, to provide technical reference for engineering material selection.

1. Differences in raw materials and structures

Short-filament geotextile is formed by a three-dimensional needle punching process using 100% polyester short fibers. The fiber length is controlled at 5-10cm, and a three-dimensional pore structure is formed by three-dimensional cross-linking. Ordinary geotextiles (usually referring to filament geotextiles) use continuous polyester filaments, with a single filament length of up to several thousand meters, and a two-dimensional layered structure is formed by laying a net and needle punching. This fundamental difference leads to a porosity of 93-95% for short-filament geotextiles, which is significantly higher than the 85-88% of filament geotextiles, providing better innate conditions for engineering drainage.

2. Comparison of mechanical properties

Experimental data show that among products of the same specifications (such as 400g/m²), the longitudinal breaking strength of short-filament geotextiles is 12.5kN/m and the transverse breaking strength is 10.8kN/m, which is about 30% lower than that of filament products of the same level. However, its CBR bursting strength reaches 2400N, which is basically the same as that of long-filament cloth. It is worth noting that the thickness of short-filament cloth is 3.8mm, which is 0.5mm more than that of long-filament cloth. This structural characteristic gives it a special advantage in puncture resistance and is particularly suitable for the protection of the bottom anti-seepage layer of landfills.

3. Division of hydraulic characteristics

The permeability coefficient test shows that the vertical permeability coefficient of short-filament geotextile reaches 0.2cm/s, which is 1.6 times that of long-filament products. This difference comes from its three-dimensional pore structure. In actual engineering, the water conduction capacity of short-filament cloth can be increased by 40%, and it performs well in scenarios that require rapid drainage, such as tailings dam drainage systems and roadbed capillary water blocking layers. However, long-filament cloth has better fiber continuity and better anti-filtration retention, and is suitable for long-term water pressure environments such as river slope protection.

4. Engineering Economic Analysis

From the perspective of the full life cycle cost, the market price of short-filament geotextile is 15-20% lower than that of long-filament products, but its durability index (82% strength retention after 2000 hours of ultraviolet irradiation) is slightly lower than 88% of long-filament cloth. It is recommended to give priority to short-filament cloth in concealed projects (such as underground drainage systems), and use long-filament products in exposed parts (such as slope protection). Comparative data of a highway project show that reasonable combination can reduce the overall material cost by 12% while ensuring that the engineering performance meets the standards.

Conclusion:

Short-filament geotextile has outstanding drainage efficiency and puncture resistance due to its unique three-dimensional structure, while long-filament products have more advantages in mechanical strength and durability. Engineering selection should comprehensively consider factors such as hydraulic requirements, mechanical loads, environmental exposure and cost control. If necessary, a composite use plan can be adopted to achieve the best engineering benefits. With the development of material modification technology, the UV resistance of new short-filament geotextiles has been improved to 85%, which may change the traditional material selection strategy.