VIT 20 - Geotextile Opening Size Tester (Dry Sieving)

Geotextile Opening Size Tester (Dry Sieving), to determine the apparent opening size (AOS) of a geotextile by sieving glass beads passing through a geotextile sample.
A geotextile specimen is placed in a sieve frame, and sized glass beads are placed on the geotextile surface. The geotextile and frame are shaken laterally so that the jarring motion will induce the beads to pass through the test specimen. The procedure is repeated on the same specimen with various size glass beads until its apparent opening size has been determined.


  • Panasonic (Japan) servo motor and driving system
  • Heavy-duty base ensures stable and quiet test/
  • Schneider (Germany) electric components and parts
  • Frequency adjustor offers a wide range of test speed
  • Includes 3 sets of stainless sieving, 10 bags of standard bead.
  • 3 specimens can be tested simultaneously

ASTM4751, GB/T 14799, JTG E50 T1144, SL/T 23, ISO 8124-1/ 8124-4

380 V 50 Hz 1000 W

210 Kg

600 x 560 x 1030mm (L x W x H)

  • Sieve diameter 200 mm
  • Amplitude 10+-/-2 mm
  • Lateral vibration frequency 220 times/min
  • Vertical vibration frequency 150 times/min
  • Radius of gyration 12+/-1mm
  • Preset time 0 ~ 60min