How is the permeability coefficient of Woven Geotextile determined?
Publish Time: 2024-10-23
The permeability coefficient of Woven Geotextile is a key indicator to measure its drainage and filtration performance in engineering.The determination of the permeability coefficient is mainly done through laboratory tests. The most commonly used method is the constant head test method. In this test, the Woven Geotextile sample is first installed in a special test device to form a certain head difference on both sides. Under the action of this head difference, water penetrates from one side of the geotextile to the other side. By measuring the amount of water passing through the geotextile in a certain period of time, combined with the cross-sectional area and head difference of the sample, the permeability coefficient is calculated according to Darcy's law (the infiltration flow is proportional to the hydraulic gradient).The specific steps include accurately measuring the effective water-passing area of the geotextile sample, which is the basic parameter for calculating the permeability coefficient. Then, under a stable head difference, the test device is turned on, and a measuring tool (such as a measuring cylinder) is used to accurately record the volume of water passing through the geotextile within a period of time (such as 1 minute or a few minutes). During the test, it is necessary to ensure that the head difference remains stable, because changes in the head difference will directly affect the measurement accuracy of the infiltration flow.In addition to the constant head test method, there is also a variable head test method. This method is suitable for geotextiles with a small permeability coefficient. In the variable head test, as the water penetrates, the head difference will gradually decrease. By recording the head difference and the corresponding time at different times, a specific formula is used to calculate the permeability coefficient.The size of the permeability coefficient is crucial to the application of Woven Geotextile in actual engineering. For example, in drainage projects, geotextiles with a large permeability coefficient can quickly drain the accumulated water and prevent the accumulated water from damaging the engineering structure. In filtration projects, the appropriate permeability coefficient can ensure that soil particles can be filtered out and water can pass smoothly, thereby achieving the dual purpose of stabilizing the soil and draining water. In short, accurately determining the permeability coefficient of Woven Geotextile is an important prerequisite for ensuring its good performance in engineering.
