Automatic Geosynthetic Thickness Gauge – QualiGTX™ TG A
The QualiGTX™ TG A automatic geosynthetic thickness gauge determines nominal thickness using seven dedicated test modes for geotextiles, geomembranes, geonets, geospacers, and drainage geocomposites. Its dual servo motor system drives a precision ball screw to lower the presser foot at a controlled speed, applying test pressures of 2 kPa, 20 kPa, or 200 kPa without operator influence. The instrument is suitable for manufacturers, independent testing laboratories, and construction quality control departments that need to verify geosynthetic roll materials against project requirements before shipment.
All seven test configurations are integrated into one instrument, eliminating the need for separate thickness gauges for geotextiles, uniform barriers, and non-uniform barriers. Interchangeable 100 cm² and 25 cm² presser feet accommodate planar materials, while specialized coaxial presser points measure polymeric and bituminous barriers, including applications involving forces as low as 0.1 N. Technicians select the required test method through the industrial touchscreen, after which the instrument automatically performs the loading sequence, dwell period, and measurement.
Thickness measurements are captured by a dial gauge offering 0.001 mm resolution over a 0 to 10 mm range. Integrated control software records each result for statistical evaluation and calculates averages across ten specimens, as required by most applicable test methods. Completed test data can also be transferred through the network to a Laboratory Information Management System (LIMS) or quality database. With overall dimensions of 1150 × 670 mm, the QualiGTX™ TG A provides extensive testing capabilities while maintaining an efficient laboratory footprint.
Automatic Geosynthetic Thickness Gauge – QualiGTX™ TG A Applications
The QualiGTX™ TG A provides reliable thickness measurement for geosynthetic materials throughout manufacturing, product development, laboratory testing, and construction quality control.
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Geotextile Manufacturing: Measures woven and nonwoven geotextile roll materials under 2 kPa pressure using the 25 cm² presser foot to verify nominal thickness against published product specifications.
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Geomembrane Production: Evaluates the thickness of uniform polymeric and bituminous barrier sheets using the flat presser foot, with coaxial presser points available for materials featuring irregular surfaces.
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Drainage Geocomposite and Geospacer QC: Uses the 100 cm² presser foot at pressures of 2, 20, and 200 kPa to assess the compression and deformation of drainage cores under different loading conditions.
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Landfill and Containment Engineering: Verifies the thickness of liner and cover system materials against project requirements before installation.
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Highway and Railway Construction: Inspects separation, filtration, and reinforcement geotextiles to confirm compliance with construction contract specifications.
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Hydraulic and Water Resources Projects: Measures canal liners, dam-facing membranes, and reservoir barriers where material thickness is an important factor in permeability calculations.
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Third-Party Testing Laboratories: Performs shipment acceptance testing across multiple geosynthetic test methods using one instrument, helping streamline laboratory accreditation requirements.
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Geosynthetic Research and Product Development: Evaluates compression characteristics across the complete pressure range when developing new drainage core designs or polymer formulations.
Standards
The QualiGTX™ TG A supports internationally recognized testing procedures for measuring geosynthetic thickness under specified pressure conditions.
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ASTM D5199 – Standard Test Methods for Measuring the Nominal Thickness of Geosynthetics
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ISO 9863 – Geosynthetics: Determination of Thickness at Specified Pressures
Automatic Geosynthetic Thickness Gauge – QualiGTX™ TG A Key Features
The QualiGTX™ TG A integrates automated servo-driven loading, specialized presser configurations, and touchscreen operation into a single laboratory instrument.
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Seven Thickness Test Modes in One Frame: Accommodates planar geosynthetics, uniform barriers, and non-uniform barriers, eliminating the need to purchase and calibrate multiple dedicated instruments.
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Dual Servo Motor Drive: Controls the upward and downward movement of the presser assembly at a consistent speed, minimizing variations associated with manual loading.
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High-Precision Ball Screw Transmission: Converts motor rotation into smooth, controlled vertical movement with minimal backlash, maintaining parallel alignment between the presser foot and reference plate.
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No Presser Foot Changeover Between Methods: Allows individual test modes to operate independently, enabling technicians to switch between testing procedures without changing hardware or repeating instrument setup.
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0.001 mm Dial Gauge Resolution: Measures thin membranes and coatings across a 0 to 10 mm range, providing the measurement precision required by applicable specifications.
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Industrial Touchscreen Controller: Combines test method selection, real-time measurement displays, and operating status on a single interface designed for laboratory and production environments.
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Multi-Specimen Averaging: Automatically calculates the average of multiple measurements on-screen, supporting the ten-specimen sampling requirements specified by geosynthetic test methods.
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Direct Result Readout and Re-Analysis: Retains completed test records for subsequent examination, allowing technicians to review measurement data without repeating the test.
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Network Upload of Test Results: Sends measurement records to a LIMS, server, or quality management database, minimizing errors associated with manual data entry.
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Purpose-Built Control Software: Features internally developed software specifically designed for geosynthetic thickness measurement, with predefined loading sequences and dwell periods for each test method.
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Compact Floor Footprint: Combines multiple testing configurations within a 1150 × 670 mm footprint, helping preserve valuable workspace in busy quality control laboratories.
Theory and Method
Geosynthetic thickness is influenced by the pressure applied during measurement rather than being a constant material dimension. Nonwoven geotextiles, geonets, and drainage cores can undergo measurable compression under load. For this reason, a meaningful thickness result must identify the applied pressure, presser foot contact area, and dwell time. Relevant test methods establish specific presser foot dimensions and loading pressures, then measure the perpendicular distance between the reference plate and presser foot after maintaining the prescribed load for a defined period. The QualiGTX™ TG A mechanically controls these testing conditions to minimize variations caused by manual operation.
The pressure applied to a specimen is determined by the relationship between the applied force and the contact area of the presser foot. The 100 cm² presser foot has a weight of 2041 g and applies a force of 20 N, producing a pressure of 2 kPa across its contact surface. Similarly, the 25 cm² presser foot weighs 510.2 g and applies a force of 5 N, generating the same 2 kPa pressure over its smaller contact area. This arrangement maintains comparable testing pressure across both configurations. The dual servo motors and precision ball screw mechanism provide additional calibrated loading to achieve pressures of 20 kPa and 200 kPa, maintaining accuracy within ±0.1 kPa and ±1 kPa, respectively.
Polymeric and bituminous barriers with irregular surfaces require an alternative measurement arrangement. A conventional flat presser foot may rest on raised surface areas rather than accurately measuring the material thickness. To address this, the instrument uses matching coaxial presser points with a radius of 1 ± 0.1 mm, allowing the contact points to seat against the specimen surface. Coaxial point forces of 0.6 N and 0.56 N are applied across three predefined test modes, covering applied loads from 0.1 N to 0.5 N and from 0.5 N to 1.0 N. The two presser points apply force through the sheet, while the dial gauge measures their resulting separation with 0.001 mm resolution.
Automatic Geosynthetic Thickness Gauge - QualiGTX™ TG A Technical Specifications
| Parameter |
Specification |
| Test Modes |
7 thickness test configurations in one instrument |
| Presser Foot Area (Geospacers and Drainage Geocomposites) |
100 cm² |
| Presser Foot Area (General Geosynthetics) |
25 cm² |
| Presser Point Radius |
1 ± 0.1 mm |
| Measuring Foot Diameter |
φ10 mm |
| 100 cm² Presser Foot Load |
20 N (2 kPa ± 0.01 kPa; foot mass 2041 g) |
| 100 cm² Foot, Second Load Stage |
20 kPa ± 0.1 kPa |
| 100 cm² Foot, Third Load Stage |
200 kPa ± 1 kPa |
| 25 cm² Presser Foot Load |
5 N (2 kPa ± 0.01 kPa; foot mass 510.2 g) |
| 25 cm² Foot, Second Load Stage |
20 kPa ± 0.1 kPa |
| 25 cm² Foot, Third Load Stage |
200 kPa ± 1 kPa |
| Coaxial Point Force, Mode 1 |
0.6 N ± 0.1 N; applied pressure 20 kPa |
| Coaxial Point Force, Mode 2 |
0.56 N + 0.05 N; applied force 0.5 N to 1.0 N |
| Coaxial Point Force, Mode 3 |
0.56 N + 0.05 N; applied load 0.1 N to 0.5 N |
| Dial Gauge Measuring Range |
0 to 10 mm |
| Dial Gauge Resolution |
0.001 mm |
| Measurement Accuracy |
0.001 mm |
| Division Value |
0.001 mm |
| Drive System |
Dual servo motors with high-precision ball screw |
| Control System |
Industrial touchscreen microcomputer with proprietary test software |
| Data Handling |
Multi-reading averaging, result storage, network upload |
| Voltage |
AC 220 V, 50 Hz (110V is also available) |
| Dimensions (W × D × H) |
1150 × 670 × 1280 mm |
| Net Weight |
180 kg |
