Apparent Opening Size Tester for Geotextiles
Sieve shaker set up for the dry glass-bead method that fixes a geotextile's apparent opening size — the O95 figure a filtration design is checked against.
Typical applications
- Filtration and separation design for geotextiles
- Soil retention checks against a design D85
- Incoming quality control on woven and non-woven geotextiles
Conforms to
- ASTM D4751—Determining apparent opening size of a geotextile
- EN ISO 12956—Geotextiles and geotextile-related products — Determination of the characteristic opening size
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Add as many products as you need and send one enquiry covering all of them, or send this item on its own. Bulk and drum quantities are quoted on request.
Worth knowing before you order
The two standards are not interchangeable. ASTM D4751 sieves dry glass beads and reports O95; EN ISO 12956 wet-sieves a graded soil and reports O90. A specification written to one cannot be closed out with the other, so tell us which one your client writes to. Everything above describes the method, not a particular model — the source is a supplier display panel that names this instrument and prints no specification for it at all: no sieve diameter, no amplitude, no timer range. Ask us and we will confirm the build, the sieve stack and the bead fractions in writing before you order.Specification
| Determines | Apparent opening size, reported as O95 in mm under ASTM D4751; characteristic opening size O90 under EN ISO 12956 |
|---|---|
| Referee method | ASTM D4751 Method A1 — dry sieving of graded glass beads through the clamped fabric |
| Consumable required | Graded glass bead fractions, sieved between runs and reused; supplied separately |
| Not covered by this instrument | ASTM D4751 Method B uses a capillary porometer, which is a different machine |
Support available
- Installation & commissioning
- Calibration
- Spares & consumables
Calibration is arranged through NABL-accredited laboratories under the relevant scope. We state the scope and the certificate number on the quotation — see what accreditation actually covers.
Related products
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Specification for Geotextile Universal Testing Machine
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Full record, hazard data and enquiry for Geotextile Universal Testing Machine →
Geotextile Permeability Apparatus (Permittivity)
Constant and falling head apparatus for water flow normal to the plane of a geotextile, giving the permittivity figure a drainage or filtration layer is specified on.
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ASTM D4491/D4491MEN ISO 11058Typical applications
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Full record, hazard data and enquiry for Geotextile Permeability Apparatus (Permittivity) →
Glass Bead Set and Separating Sieves for Apparent Opening Size
The graded glass beads and separating sieves that the dry-sieving apparent opening size method consumes — the part of an AOS rig that is bought again, not once.
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Specification for Glass Bead Set and Separating Sieves for Apparent Opening Size
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Geotextile Abrasion Tester (Sliding Block)
Loaded sliding block that abrades a geotextile against abrasive paper for a set number of cycles, so the retained strength after installation damage can be measured.
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Specification for Geotextile Abrasion Tester (Sliding Block)
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Full record, hazard data and enquiry for Geotextile Abrasion Tester (Sliding Block) →
