Research on Progressive Stabilization Filter System of Silt Foundation around Tube Well

Table 4

Silty sand influx after filtration.

Serial number	Filter material	0–2 cm from the interface (%)	2–4 cm from the interface (%)
1	U.S. water and soil conservation agency filter media	1.23	0.21
2	Terzaghi upper covered wire filter material	1.52	0.3
3	Terzaghi undercover filter material	3.65	0.84
4	Water Research Institute filter material	4.66	1.53
5	Witt filter	5.03	2.69
6	Outsourcing coarse particle filter	7.15	5.28