Geotextile Testing Instruments

Meets: - ASTM- D 5199, EN-ISO-9863-1, IS-13162-3
This is used for measuring the thickness of the geotextile. The thickness of the geosynthetic material can be measured with an accuracy of 0.001 mm (depend on the dial gauge accuracy) for thickness up to 10 mm with Foot pressure of 6.35 mm, 10 mm and 56.4 mm diameter. Dead weight mechanism is provided to apply desired pressure varying from 2, 20 to 200 kPa. Surface plate is grounded and is rust free to enable reproducible results.

Specification

• Thickness measuring resolution 0.01 mm or as desired
• Thickness measuring range 0.01-12.5 mm or as desired

Meets: - EN-ISO-13433-2006, BS6906: Part 6
Method to determine the resistance of geosynthetics to penetration by steel cone dropped from a fixed height, as a simulation of dropping sharp stones on their surface. Generally applicable to all geosynthetics. However, the test principle may not be applicable to some types of products. The specimen is clamped between two steel rings. A steel cone (45° tip angle, 1000 g) is dropped from a height of 500 mm onto the centre of the specimen. The degree of penetration is measured by insertion of a graduated cone into the hole.

Note: - Electrically cone release facility also available

Permeability of a geotextile must be substantially greater than that of the protected soil, so that water can pass freely from the soil through the fabric without build up of hydro static pressure. A high value of the permeability of the geotextile also infers that partial clogging will not reduce the permeability. The constant head test is carried out using a head of 50 mm of water.

Essential Accessories
Overhead Tank
Loading unit, 300-kPa capacity
Cross Permeability Apparatus

Meets: - ASTM- D 4491 – 99a, IS-14324
These test methods cover procedures for determining the hydraulic conductivity (water permeability) of geotextiles in terms of permittivity under standard testing conditions, in the uncompressed state. Included are two procedures: the constant head method and the falling head method.

In Constant Head Test:- A head of 50 mm water is maintained on the geo textile throughout the test. The quantity of flow is measured versus time. The constant head test is used when the flow rate of water through the geotextile is so large that it is difficult to obtain readings of head change versus time in the falling head test.

In Falling Head Test:- A column of water is allowed to flow through the geo textile and reading of head changes versus time is taken. The flow rate of water through the geo textile shall be slow enough to obtain accurate readings.

• Sample Size: - 50 mm
• Head can be maintain of the sample : up to 40 cm
• Suitable for Both type of test :- Constant Head and Falling Head.

De-Aired Tank is designed to remove dissolved gasses from ordinary clean water. The apparatus consists of a closed cylinder with hose attached to vacuum pump provided, which is controlled by PID controller.

Capacity : -20 liter

Meets: - ASTM D4751-87, BS-6906-2, IS-14294
The test involves sieving rounded particle sizes for which 5% or less by weight pass through the geotextile. The Apparent Opening Size (AOS) is defined as ‘Retained On’ size of that fraction expressed as a standard sieve number (size). The test is widely used for relative comparison amongst the geotextiles. Thus AOS is a means of correlating geotextile pore structure to an equivalent screen mesh size. The apparatus consist of a 20 cm dia brass frame with clamp, a receiver and a lid Dry Sieve Test Apparatus.

The apparatus comprises a sieving unit, which allows testing of a specimen with an exposed sieving area corresponding having 148 mm diameter with a supported Grid of 1.4 mm diameter and mesh size of (10±1)mm to support the specimen during the test to avoid excessive deformation having the nozzle for discharge of water Fixing on the acrylic sheet cover for viewing the sample during test. The complete set is provided with the pan which has the drain nozzle for collate the water after test.

To make the process of sieving easier and quicker, electrically operated mechanical table top type sieve shakers are offered for dry sieving. These Sieve Shakers are popularly used not only in soil laboratories but also dry sieving the geotextile testing

ELECTROMAGNETIC SIEVE SHAKER, which have been developed applying the latest technological advances of power control. The sieve shakers microcontroller is used to set both the process time from 1 min to 99 min and the amplitude from 0.5 to 3.5.

The Beads of the following size is available in One Kg pack

• Rounded Beads, made of glass, size 0.85 mm (passing 1 mm and retained at 0.85 mm)
• Rounded Beads, made of glass, size 0.425 mm (passing 0.85 mm and retained at 0.425 mm)
• Rounded Beads, made of glass, size 0.25 mm (passing 0.425 mm and retained at 0.25 mm)
• Rounded Beads, made of glass, size 0.18 mm (passing 0.25 mm and retained at 0.18 mm)
• Rounded Beads, made of glass, size 0.15 mm (passing 0.18 mm and retained at 0.15 mm)
• Rounded Beads, made of glass, size 0.075 mm (passing 0.15 mm and retained at 0.075 mm)

Water supply system is designed to spray the water on the sample it is provided with the flow control valve on the front and with two indicator one for power supply on and one for pump on.

This test is necessary for drainage application. The permeameters can be of parallel flow or radial flow type. In either case, flow occurs along the plane of the permeamatre. In the apparatus, flow occurs radically outwards, from a central hole to the periphery of a circular specimen. The transmissivity is defined as the volumetric rate of flow per unit width of geotextile and unit hydraulic head.

Essential Accessories
Overhead Tank
Loading unit, 300 kPa capacity