{"title":"Apparent Opening Size (AOS) Tester","description":"\u003ch2\u003eApparent Opening Size Testers for Geotextiles | ASTM D4751\u003c\/h2\u003e\n\u003cp\u003eGeotextile filtration performance depends on the size of the openings within the fabric. The QualiGTX™ Apparent Opening Size (AOS) Tester evaluates this property by passing graded glass beads through a geotextile under dry sieving conditions. The resulting O95 value represents the approximate largest soil particle that can pass through the fabric, giving engineers a basis for assessing its ability to retain soil while maintaining water flow.\u003c\/p\u003e\n\u003cp\u003eSpecified in ASTM D4751, this test provides essential data for selecting geotextiles used in filtration and separation systems. Highway construction projects, geotextile manufacturers, and independent testing laboratories use these measurements to verify material characteristics, assess product consistency, and determine suitability for specific soil conditions.\u003c\/p\u003e\n\u003cp\u003eTo accommodate different testing workloads and laboratory setups, Qualitest offers three models in the QualiGTX™ AOS Tester series. All configurations follow the same dry sieving procedure for single-layer geotextiles and related products. The available models differ in their operating systems, number of specimens handled per batch, and overall equipment footprint, allowing laboratories to select a configuration that matches their testing requirements.\u003c\/p\u003e\n\u003ch2\u003eApplications\u003c\/h2\u003e\n\u003cp\u003eAccurate apparent opening size measurements help determine whether a geotextile provides the required balance between soil retention and water passage. These results are important when selecting filtration, separation, and stabilization materials for construction and environmental projects.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eHighway and Airfield Construction: Evaluates whether separation geotextiles prevent fine subgrade particles from migrating into the granular base layer under traffic loads, helping maintain the separation between pavement foundation materials.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eGeotextile Manufacturing Quality Control: Checks finished fabric rolls against their specified O95 values, allowing manufacturers to verify that production materials meet the pore-size requirements stated in product data sheets.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDrainage and Filter Design: Provides the apparent opening size measurements engineers need to compare with soil d85 values when selecting geotextiles for drainage and filtration applications.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDams, Canals, and Levees: Assesses geotextile filter materials used behind riprap, beneath revetment structures, and around toe drainage systems, where soil retention and water movement must work together.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eErosion and Sediment Control: Determines whether silt fences, scour protection aprons, and slope stabilization fabrics have suitable opening sizes before they are installed at construction and erosion-control sites.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eLandfill and Containment Systems: Verifies pore-size characteristics of filtration and cushioning geotextiles used in leachate collection systems and landfill cover assemblies.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIndependent Testing Laboratories: Supports routine apparent opening size testing for material specifications, regulatory requirements, and certification programs.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eApparent Opening Size Tester Range\u003c\/h2\u003e\n\u003cp\u003eThe QualiGTX™ AOS series includes three models designed for different laboratory workloads, from periodic material verification to high-volume incoming quality inspections. All configurations feature a 200 mm sieve column, a 400 mm stack height, and a 0.37 kW drive, providing a consistent testing arrangement across the product range.\u003c\/p\u003e\n\u003ctable class=\"table table-style-align-center\" align=\"center\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eControl\u003c\/th\u003e\n\u003cth\u003eCapacity and Accessories\u003c\/th\u003e\n\u003cth\u003eSize and Weight\u003c\/th\u003e\n\u003cth\u003eBest Suited To\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eQualiGTX™ AOS T\u003c\/td\u003e\n\u003ctd\u003eColor touchscreen\u003c\/td\u003e\n\u003ctd\u003e5 specimens per cycle; 5 pressing rings and a graded glass bead set included; low-noise drive\u003c\/td\u003e\n\u003ctd\u003e700 × 620 × 1360 mm, 160 kg\u003c\/td\u003e\n\u003ctd\u003eDesigned for laboratories handling regular incoming material inspections, with guided touchscreen operation for consistent results across operators. Its low-noise drive also makes it suitable for shared laboratory spaces where quieter equipment operation is preferred.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eQualiGTX™ AOS M\u003c\/td\u003e\n\u003ctd\u003eManual controls\u003c\/td\u003e\n\u003ctd\u003e5 specimens per cycle; 5 pressing rings, 5 stainless steel sieve pans, and a graded glass bead set included\u003c\/td\u003e\n\u003ctd\u003e770 × 650 × 1060 mm, 80 kg\u003c\/td\u003e\n\u003ctd\u003eSuited to laboratories processing five specimens per batch that need separate bead collection for each sample and individual weighing after testing. Manual controls provide straightforward operation without the complexity of a programmable interface.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eQualiGTX™ AOS DSM\u003c\/td\u003e\n\u003ctd\u003eMotorized shaker\u003c\/td\u003e\n\u003ctd\u003eStandard sieve column configuration\u003c\/td\u003e\n\u003ctd\u003e750 × 480 × 850 mm, 70 kg\u003c\/td\u003e\n\u003ctd\u003eDesigned for laboratories with restricted bench or floor space, particularly where AOS testing is performed periodically as part of a broader geosynthetic testing program. Its compact, lightweight construction provides a practical solution without requiring dedicated space for frequent testing.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2\u003eHow to Choose the Right Apparent Opening Size Tester\u003c\/h2\u003e\n\u003cp\u003eSelecting the appropriate AOS tester depends on specimen throughput, operating preferences, available laboratory space, and testing frequency.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eFor high-volume testing and multiple operators: The QualiGTX™ AOS T features touchscreen operation, helping maintain consistent testing procedures across different operators and work shifts.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFor batches of five specimens with straightforward operation: The QualiGTX™ AOS M combines manual controls with stainless steel collection pans. These pans keep the glass beads from each specimen separate, allowing individual weighing after testing.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFor laboratories with limited floor space: The QualiGTX™ AOS DSM offers the most compact and lightweight configuration in the series, weighing just 70 kg.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFor shared laboratory and sample preparation areas: The QualiGTX™ AOS T uses a low-noise drive to minimize the tapping sounds commonly associated with conventional sieve shakers.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFor occasional testing and material verification: The QualiGTX™ AOS DSM provides the required testing method in a compact configuration, with the lowest equipment footprint and cost of ownership in the range.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eBefore placing an order: Verify electrical compatibility with your laboratory's power supply. All three models are specified for 380 V operation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWhy Choose Qualitest for Your Apparent Opening Size Tester\u003c\/h2\u003e\n\u003cp\u003eQualitest North America provides testing and measurement equipment for manufacturers, quality control departments, and independent laboratories, supported by responsive technical assistance and calibration services.\u003c\/p\u003e\n\u003cp\u003eThe QualiGTX™ Apparent Opening Size Tester series is designed to deliver dependable measurements in accordance with established testing procedures. With three configurations available, Qualitest helps laboratories select equipment that matches their specimen requirements, applicable standards, and testing workloads.\u003c\/p\u003e\n\u003cp\u003eFrom choosing the appropriate model to installation and ongoing technical assistance, our team provides support throughout the equipment ownership process.\u003c\/p\u003e\n\u003ch2\u003eRequest a Quote\u003c\/h2\u003e\n\u003cp\u003eWhether you need an AOS tester for periodic geotextile verification or continuous incoming material inspection, Qualitest can help identify the right configuration for your laboratory. Share your geotextile types, expected monthly testing volume, and available installation space so our team can recommend a suitable model.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/qualitest.us\/pages\/contact\"\u003eContact the Qualitest team\u003c\/a\u003e for pricing information and current lead times.\u003c\/p\u003e","products":[{"product_id":"touch-screen-geotextile-apparent-opening-size-aos-tester","title":"Touch-screen Geotextile Apparent Opening Size (AOS) Tester","description":"\u003ch2\u003eTouchscreen Geotextile Apparent Opening Size (AOS) Tester – QualiGTX™ AOS T\u003c\/h2\u003e\n\u003cp\u003eThe QualiGTX™ AOS T measures the apparent opening size of single-layer geotextiles and other geosynthetic materials\n    through a controlled dry sieving process. Using graded glass beads, it identifies the characteristic pore size of a\n    fabric and determines whether its openings provide the required balance between soil retention and water passage.\n    This measurement is essential for civil engineering laboratories, geosynthetic manufacturers, and highway\n    quality-control teams evaluating filter fabric performance.\u003c\/p\u003e\n\u003cp\u003eDesigned for different fabric constructions, the tester accommodates materials ranging from needle-punched nonwovens\n    to woven monofilament geotextiles. Its color touchscreen provides centralized control of the sieving process,\n    allowing operators to configure and monitor testing through a single interface.\u003c\/p\u003e\n\u003cp\u003eFor higher testing throughput, the QualiGTX™ AOS T includes five specimen pressing rings, allowing five fabric\n    samples to be prepared and tested during one cycle. Its 200 mm sieve column accommodates a stacked frame height of\n    up to 400 mm, eliminating the need to divide a full test assembly into multiple runs. The low-noise drive helps\n    maintain a suitable working environment in shared laboratory spaces, while the supplied graded glass bead set\n    provides the reference materials needed to begin testing.\u003c\/p\u003e\n\u003cp\u003eConsistent mechanical movement is essential for obtaining reliable apparent opening size measurements. The instrument\n    maintains horizontal oscillation at 221 cycles per minute and vertical tapping at 147 impacts per minute. An 8 mm\n    amplitude and 12.5 mm radius of gyration establish a consistent agitation pattern throughout the test. By\n    maintaining these operating conditions, the tester supports comparable O95 measurements across operators, work\n    shifts, production batches, and laboratories. The resulting data helps engineers select appropriate geotextile\n    filters for drainage, soil separation, and erosion-control applications.\u003c\/p\u003e\n\u003ch2\u003eQualiGTX™ AOS T Applications\u003c\/h2\u003e\n\u003cp\u003eThe QualiGTX™ AOS T is suitable for laboratories and engineering projects that require accurate assessment of\n    geotextile pore size to evaluate filtration performance and soil retention.\u003c\/p\u003e\n\u003cul\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eGeotextile Production and Quality Assurance: Manufacturers can assess woven and nonwoven fabric batches to\n            verify that measured opening sizes remain within established product specifications before materials are\n            released.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eHighway and Pavement Construction: Engineers can evaluate separation geotextiles used between subgrade soils\n            and aggregate base layers to determine whether the fabric prevents fine soil particles from migrating into\n            the pavement structure.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eDrainage and Filtration Engineering: Measured O95 values can be compared with the d85 particle size of the\n            retained soil to identify a suitable geotextile grade for filtration systems.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eDams, Levees, and Canal Construction: Testing helps verify the suitability of filter fabrics installed behind\n            riprap, beneath revetments, and around drainage collectors in hydraulic structures.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eCoastal Protection and Erosion Management: The instrument evaluates geotextiles intended for scour\n            protection, shoreline armoring, and silt fence installations.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eLandfill and Environmental Containment Systems: Laboratories can check the pore size of protective and\n            filtration layers used in leachate collection systems to assess their filtration characteristics.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eIndependent and Accredited Testing Laboratories: Third-party facilities can perform routine apparent opening\n            size measurements for construction contractors, material specifiers, and product certification programs.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eGeosynthetic Research and Material Development: Researchers can investigate how fiber arrangement, denier,\n            and bonding techniques influence the measured pore size of newly developed geotextile fabrics.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eQualiGTX™ AOS T Key Features\u003c\/h2\u003e\n\u003cp\u003eThe QualiGTX™ AOS T integrates automated touchscreen operation, controlled specimen agitation, and a multi-sample\n    sieve arrangement to support efficient and consistent geotextile opening size testing.\u003c\/p\u003e\n\u003cul\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eColor Touchscreen Operation: Operators can configure the test duration and monitor the complete sieving cycle\n            through a centralized display, simplifying operation compared with conventional multi-knob control systems\n            and reducing training requirements.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eFive-Specimen Testing Capacity: The system processes five geotextile samples in one cycle, increasing\n            laboratory throughput and reducing the time required for incoming fabric batch inspections.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eFive Specimen Pressing Rings Included: Dedicated pressing rings hold each sample flat without introducing\n            tension, providing consistent conditions for glass bead interaction with the fabric.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eLow-Noise Drive Mechanism: The drive system limits operating noise associated with mechanical sieve tapping,\n            making the instrument suitable for laboratories located near offices and sample preparation areas.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eGraded Glass Bead Set Supplied: The included reference beads provide the materials required for dry sieving,\n            allowing testing to begin without separately sourcing the specified media.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003e200 mm Sieve Column and 400 mm Stack Capacity: The column accommodates sieve frames and collection pans with\n            a maximum stacked height of 400 mm, supporting complete test assemblies in a single run.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eConsistent Oscillation and Tapping Frequencies: Fixed operating rates of 221 horizontal oscillations and 147\n            vertical taps per minute help maintain comparable testing conditions across different operators, shifts, and\n            laboratory locations.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eControlled 8 mm Amplitude and 12.5 mm Radius of Gyration: These defined movement parameters establish the\n            agitation pattern needed to distribute glass beads consistently across the specimen surface.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eHeavy-Duty Floor-Standing Construction: With a total mass of 160 kg, the rigid frame helps absorb mechanical\n            vibration during tapping and maintains sieve column stability throughout the testing cycle.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eTheory and Test Method\u003c\/h2\u003e\n\u003cp\u003eThe apparent opening size of a geotextile is determined indirectly by observing how effectively the fabric allows\n    glass beads of known diameters to pass through its openings. In the dry sieving method, a specimen is secured inside\n    a sieve frame, and a measured quantity of glass beads from a specific size fraction is distributed over its surface.\n    The assembled unit then undergoes controlled agitation for a predetermined period.\u003c\/p\u003e\n\u003cp\u003eDuring this process, beads with diameters smaller than the fabric openings can pass through the geotextile and\n    collect in the pan positioned underneath. Beads that cannot pass through remain above the specimen. The collected\n    material is subsequently weighed to establish the percentage of the original bead charge that passed through the\n    fabric.\u003c\/p\u003e\n\u003cp\u003eThe procedure is repeated using progressively larger bead fractions to develop a relationship between bead diameter\n    and percentage passing. From this distribution, the apparent opening size, expressed as O95, is determined as the\n    bead diameter corresponding to 5% or less passing through the specimen. This measurement provides an estimate of the\n    largest soil particle size that can pass through the geotextile and serves as an important parameter in filter\n    retention calculations.\u003c\/p\u003e\n\u003cp\u003eGeotextile selection requires balancing particle retention with water transmission. A fabric with a smaller O95 can\n    retain finer soil particles but may restrict water flow, whereas a larger O95 generally allows easier drainage while\n    increasing the risk of fine soil migration and piping.\u003c\/p\u003e\n\u003cp\u003eThe dry sieving process relies on two coordinated movements to produce representative results. Horizontal rotary\n    oscillation moves the glass bead layer across the specimen, exposing the beads to different fabric openings rather\n    than allowing them to remain concentrated in the same positions. Vertical tapping introduces impact energy that\n    helps release beads lodged within the geotextile structure.\u003c\/p\u003e\n\u003cp\u003eThe QualiGTX™ AOS T maintains fixed horizontal and vertical movement rates together with an 8 mm amplitude to ensure\n    consistent agitation conditions. Changes in these parameters affect the energy transferred to the bead layer and can\n    consequently influence the measured apparent opening size. Maintaining controlled operating conditions is therefore\n    essential for obtaining repeatable O95 results.\u003c\/p\u003e\n\u003ch2\u003eTouch-screen Geotextile Apparent Opening Size (AOS) Tester - QualiGTX™ AOS T Technical Specifications\u003c\/h2\u003e\n\n\u003ctable class=\"table table-style-align-center\" align=\"center\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n    \u003cthead\u003e\n        \u003ctr\u003e\n            \u003cth\u003eParameter\u003c\/th\u003e\n            \u003cth\u003eSpecification\u003c\/th\u003e\n        \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eTest Principle\u003c\/td\u003e\n            \u003ctd\u003eDry sieving, single-layer geotextile and related products\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eMeasured Property\u003c\/td\u003e\n            \u003ctd\u003eApparent opening size (AOS \/ O95)\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Diameter\u003c\/td\u003e\n            \u003ctd\u003e200 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Stack Height\u003c\/td\u003e\n            \u003ctd\u003e400 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Base Amplitude\u003c\/td\u003e\n            \u003ctd\u003e8 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Oscillation Rate\u003c\/td\u003e\n            \u003ctd\u003e221 oscillations\/min\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eTapping Rate\u003c\/td\u003e\n            \u003ctd\u003e147 taps\/min\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eRadius of Gyration\u003c\/td\u003e\n            \u003ctd\u003e12.5 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSpecimen Capacity\u003c\/td\u003e\n            \u003ctd\u003e5 specimens per cycle\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eControl System\u003c\/td\u003e\n            \u003ctd\u003eColor touchscreen\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eMotor Power\u003c\/td\u003e\n            \u003ctd\u003e0.37 kW\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eVotlage\u003c\/td\u003e\n            \u003ctd\u003eAC 380 V, 50 Hz\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eDimensions (W × D × H)\u003c\/td\u003e\n            \u003ctd\u003e700 × 620 × 1360 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eWeight\u003c\/td\u003e\n            \u003ctd\u003e160 kg\u003c\/td\u003e\n        \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eIncluded Configuration\u003c\/h3\u003e\n\u003ctable class=\"table table-style-align-center\" align=\"center\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n    \u003cthead\u003e\n        \u003ctr\u003e\n            \u003cth\u003eItem\u003c\/th\u003e\n            \u003cth\u003eQuantity\u003c\/th\u003e\n            \u003cth\u003eDescription\u003c\/th\u003e\n        \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eStandard Glass Bead Set\u003c\/td\u003e\n            \u003ctd\u003e1 set\u003c\/td\u003e\n            \u003ctd\u003eGraded reference beads for dry sieving determinations\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSpecimen Pressing Rings\u003c\/td\u003e\n            \u003ctd\u003e5\u003c\/td\u003e\n            \u003ctd\u003eClamps geotextile specimens flat within the sieve frames\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eTouchscreen Control Unit\u003c\/td\u003e\n            \u003ctd\u003e1\u003c\/td\u003e\n            \u003ctd\u003eSets and monitors the sieving cycle\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Column Assembly\u003c\/td\u003e\n            \u003ctd\u003e1\u003c\/td\u003e\n            \u003ctd\u003e200 mm frames with 400 mm stacking capacity\u003c\/td\u003e\n        \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"Qualitest USA LC","offers":[{"title":"Default Title","offer_id":53604179149111,"sku":null,"price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0786\/1859\/1543\/files\/touch-screen-geotextile-apparent.webp?v=1794479422"},{"product_id":"manual-geotextile-apparent-opening-size-aos-tester","title":"Manual Geotextile Apparent Opening Size (AOS) Tester","description":"\u003ch2\u003eManual Geotextile Apparent Opening Size (AOS) Tester – QualiGTX™ AOS M\u003c\/h2\u003e\n\u003cp\u003eThe QualiGTX™ AOS M determines the apparent opening size of single-layer geotextiles and related geosynthetic\n    materials through dry sieving with graded glass beads. Its manually operated controls regulate a motor-driven sieve\n    shaker, allowing laboratories to obtain O95 measurements without the setup and maintenance associated with\n    programmable interfaces. Designed for woven, nonwoven, and composite geotextiles, the instrument supports material\n    evaluation across commercially available fabric constructions. Manufacturers, contractors, quality-control\n    departments, and independent testing laboratories rely on these measurements to assess whether a geotextile's pore\n    structure is appropriate for the soil it must retain.\u003c\/p\u003e\n\u003cp\u003eThe instrument accommodates five specimens during a single testing cycle. Individual pressing rings secure each\n    fabric within the sieve column, while five stainless steel sieve pans collect the glass beads passing through the\n    respective specimens. A graded glass bead set is included, providing the reference material required for testing.\n    The 200 mm sieve column supports a total stack height of 400 mm, providing sufficient capacity for all five specimen\n    frames and collection pans in one operation. This multi-specimen arrangement allows laboratories to evaluate five\n    fabrics simultaneously rather than conducting separate tests for each sample.\u003c\/p\u003e\n\u003cp\u003eThe shaker operates with specified agitation rates and defined tolerances to maintain consistent testing conditions.\n    Its sieve base produces 220 oscillations per minute (±10) and 150 vertical impacts per minute (±10), with a 10 mm\n    amplitude and 12 mm radius of gyration. These operating limits provide measurable reference points for checking\n    equipment performance during commissioning and routine verification against the applicable test method. With an\n    overall weight of 80 kg, the instrument offers a practical configuration for standard laboratory workspaces.\u003c\/p\u003e\n\u003ch2\u003eManual Geotextile Apparent Opening Size (AOS) Tester – QualiGTX™ AOS M Applications\u003c\/h2\u003e\n\u003cp\u003eThe apparent opening size of a geotextile determines how effectively it can retain soil particles while allowing\n    water to pass through. Measuring this property helps engineers and material specialists select appropriate fabrics\n    for separation, filtration, drainage, and erosion-control applications.\u003c\/p\u003e\n\u003cul\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eIncoming Geotextile Quality Inspection: Evaluates incoming fabric batches against the manufacturer's declared\n            O95 value, helping quality-control personnel identify materials that do not meet specified requirements\n            before installation.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eRoad and Railway Subgrade Stabilization: Assesses separation geotextiles used between subgrade soils and\n            aggregate base layers, ensuring the fabric can restrict the upward migration of fine particles under\n            repeated traffic loads.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eSubsurface Drainage Systems: Provides the opening size data needed to select compatible filter fabrics for\n            trench drainage, roadway edge drains, and collector pipe installations.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eDams, Canals, and Hydraulic Structures: Evaluates filtration materials placed behind riprap, beneath\n            revetments, and around toe drains to support soil retention in dams, levees, and canal protection systems.\n        \u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eCoastal Protection and Slope Erosion Control: Determines the suitability of geotextiles used in scour\n            protection aprons, gabion linings, and silt fences before deployment in exposed environments.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eLandfill and Waste Containment Applications: Verifies the pore characteristics of filtration and protective\n            geotextile layers incorporated into leachate collection arrangements and landfill cover systems.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eThird-Party Material Testing: Performs routine apparent opening size assessments for independent laboratories\n            supporting engineering specifications, regulatory agencies, and product certification programs.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eGeotextile Product Development: Helps manufacturers examine how fiber diameter, needling density, and\n            calendering conditions influence the resulting pore structure, supporting product comparisons and material\n            development.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eManual Geotextile Apparent Opening Size (AOS) Tester – QualiGTX™ AOS M Key Features\u003c\/h2\u003e\n\u003cp\u003eThe QualiGTX™ AOS M combines direct manual controls, five-specimen testing capacity, and controlled mechanical\n    agitation in a configuration designed for dry sieving applications.\u003c\/p\u003e\n\u003cul\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eDirect Manual Controls: Provides straightforward operation through dedicated controls rather than\n            software-driven menus, simplifying operator training and eliminating software maintenance requirements.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eMotorized Sieve Shaker: Uses a 0.37 kW motor to generate consistent oscillating and tapping movements\n            throughout the test cycle, providing controlled mechanical agitation instead of manual shaking.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eFive-Specimen Testing Capacity: Allows five geotextile samples to undergo testing in the same cycle, reducing\n            the time required for batch inspection and routine laboratory work.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eFive Stainless Steel Collection Pans: Separates the beads passing through each specimen for individual\n            weighing while providing corrosion resistance during cleaning and routine handling.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eFive Specimen Pressing Rings: Secures each fabric flat within its respective frame without introducing\n            tension, helping maintain consistent conditions across all five specimens.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eComplete Graded Glass Bead Set: Includes the reference beads required for apparent opening size measurements,\n            allowing laboratories to begin testing without sourcing a separate bead set.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003e200 mm Sieve Column and 400 mm Stack Height: Provides room for the complete arrangement of specimen frames\n            and collection pans, allowing all five samples to be processed in one cycle.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eDefined Agitation Tolerances: Maintains an oscillation rate of 220 cycles per minute (±10) and a tapping rate\n            of 150 impacts per minute (±10), supporting consistent test conditions between operators and laboratories.\n        \u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003eControlled Motion Geometry: Combines a 10 mm amplitude with a 12 mm radius of gyration to establish the\n            prescribed movement pattern and distribute glass beads across the specimen surface.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n    \u003cli\u003e\n\n\n        \u003cp\u003e80 kg Compact Construction: Offers a manageable equipment footprint for conventional laboratory layouts and\n            makes repositioning between workbenches easier than with heavier sieve-shaking equipment.\u003c\/p\u003e\n\n\n    \u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eTheory and Test Method\u003c\/h2\u003e\n\u003cp\u003eThe dry sieving method determines the apparent opening size of a geotextile by evaluating how glass beads of known\n    sizes pass through its structure. Rather than measuring individual pores directly, the procedure establishes a\n    relationship between bead diameter and the proportion passing through the fabric.\u003c\/p\u003e\n\u003cp\u003eTesting begins by securing a geotextile specimen in a sieve frame and placing a weighed quantity of glass beads from\n    a narrowly graded size fraction on its surface. The shaker then agitates the assembly for the specified testing\n    period. Beads smaller than the openings they encounter can pass through the fabric and collect in the sieve pan\n    below. The collected material is subsequently weighed to establish the percentage of the original bead charge that\n    passed through the specimen.\u003c\/p\u003e\n\u003cp\u003eThe procedure is repeated using progressively larger bead fractions to generate a series of passing percentages.\n    These measurements are plotted against the corresponding bead diameters to establish a particle-size distribution\n    curve. The apparent opening size, designated O95, is determined at the diameter corresponding to 5% passing or less.\n    This value represents an approximate upper particle-size threshold for material passing through the geotextile.\u003c\/p\u003e\n\u003cp\u003eO95 is an important consideration when selecting filtration fabrics. An opening size that is too large can allow soil\n    fines to migrate through the geotextile, potentially compromising the stability of the surrounding structure.\n    Conversely, openings that are too small can become blocked by retained particles, restricting water movement and\n    reducing drainage performance.\u003c\/p\u003e\n\u003cp\u003eThe mechanical action of the sieve shaker plays a critical role in obtaining reliable measurements. Horizontal\n    circular oscillation moves the glass bead layer across the specimen, exposing the beads to a representative\n    distribution of fabric openings rather than concentrating contact in one area. Vertical tapping provides additional\n    impact energy, helping dislodge beads that become temporarily lodged within the fiber network.\u003c\/p\u003e\n\u003cp\u003eBoth movements must remain within their specified operating ranges because variations in oscillation and tapping\n    rates alter the energy transferred to the bead layer. These changes can affect bead passage and shift the resulting\n    apparent opening size. The QualiGTX™ AOS M maintains controlled agitation through its defined operating tolerances,\n    supporting repeatable testing conditions and comparable O95 measurements.\u003c\/p\u003e\n\n\u003ch2\u003eManual Geotextile Apparent Opening Size (AOS) Tester - QualiGTX™ AOS M Technical Specifications\u003c\/h2\u003e\n\u003ctable class=\"table\" style=\"width: 100%;\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n    \u003cthead\u003e\n        \u003ctr\u003e\n            \u003cth\u003eParameter\u003c\/th\u003e\n            \u003cth\u003eSpecification\u003c\/th\u003e\n        \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eTest Principle\u003c\/td\u003e\n            \u003ctd\u003eDry sieving, single-layer geotextile and related products\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eMeasured Property\u003c\/td\u003e\n            \u003ctd\u003eApparent opening size (AOS \/ O95)\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Diameter\u003c\/td\u003e\n            \u003ctd\u003e200 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Stack Height\u003c\/td\u003e\n            \u003ctd\u003e400 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Base Amplitude\u003c\/td\u003e\n            \u003ctd\u003e10 mm ± 2 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Oscillation Rate\u003c\/td\u003e\n            \u003ctd\u003e220 oscillations\/min ± 10\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eTapping Rate\u003c\/td\u003e\n            \u003ctd\u003e150 taps\/min ± 10\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eRadius of Gyration\u003c\/td\u003e\n            \u003ctd\u003e12 mm ± 1 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSpecimen Capacity\u003c\/td\u003e\n            \u003ctd\u003e5 specimens per cycle\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eControl Type\u003c\/td\u003e\n            \u003ctd\u003eManual\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eMotor Power\u003c\/td\u003e\n            \u003ctd\u003e0.37 kW\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eVotlage\u003c\/td\u003e\n            \u003ctd\u003e380 V\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eDimensions (W × D × H)\u003c\/td\u003e\n            \u003ctd\u003e770 × 650 × 1060 mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eWeight\u003c\/td\u003e\n            \u003ctd\u003e80 kg\u003c\/td\u003e\n        \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eIncluded Configuration\u003c\/h3\u003e\n\u003ctable class=\"table\" style=\"width: 100%;\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n    \u003cthead\u003e\n        \u003ctr\u003e\n            \u003cth\u003eItem\u003c\/th\u003e\n            \u003cth\u003eQuantity\u003c\/th\u003e\n            \u003cth\u003eDescription\u003c\/th\u003e\n        \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eStandard Glass Bead Set\u003c\/td\u003e\n            \u003ctd\u003e1 set\u003c\/td\u003e\n            \u003ctd\u003eGraded reference beads for dry sieving determinations\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSpecimen Pressing Rings\u003c\/td\u003e\n            \u003ctd\u003e5\u003c\/td\u003e\n            \u003ctd\u003eClamps geotextile specimens flat within the sieve frames\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eStainless Steel Sieve Pans\u003c\/td\u003e\n            \u003ctd\u003e5\u003c\/td\u003e\n            \u003ctd\u003eCollects beads passing through each specimen for individual weighing\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n            \u003ctd\u003eSieve Column Assembly\u003c\/td\u003e\n            \u003ctd\u003e1\u003c\/td\u003e\n            \u003ctd\u003e200 mm frames with 400 mm stacking capacity\u003c\/td\u003e\n        \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"Qualitest USA LC","offers":[{"title":"Default Title","offer_id":53604211228983,"sku":null,"price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0786\/1859\/1543\/files\/manual-geotextile-apparent-openi.webp?v=1794479796"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0786\/1859\/1543\/collections\/apparent-opening-size-aos-tester.webp?v=1794479072","url":"https:\/\/qualitest.us\/collections\/apparent-opening-size-aos-tester.oembed","provider":"Qualitest USA LC","version":"1.0","type":"link"}