Concept of Limit Soil-Retained State for Developing of Novel Filtration Criteria

Abstract

Geotextile filters have been used as substitution of granular filters for decades. Despite their technical and commercial success, the behavior of geotextile filters can be quite complex and difficult to understand, especially the erosion or clogging problems that lead to instability of a filtration system. This paper focuses on the influence of soil particle migration on the permeability of the filtration system and whether the system will be unstable due to excessive erosion of soil particles when a large opening–size geotextile is used as a filter. A series of model tests with a dimension of 120×79×25 cm under different hydraulic conditions were carried out. The microscopic image analysis method was used for the particle-grading analysis. Finally, from the experiments performed, the modified research approach for criteria for determining the instability of the filtration system due to excessive erosion of soil particles and the modified research approach for criteria for determining the limit soil-retained state were proposed and discussed.