What is the primary function of a GCL according to this standard?

To act as a hydraulic barrier, with a maximum specified hydraulic conductivity of 5 x 10⁻¹¹ m/s (Table 1).

What type of clay is specified for GCLs?

Sodium bentonite with a minimum swell index of 24 ml per 2 grams is specified (Clause 4.2).

What is the minimum required strength for a GCL?

The minimum grab tensile strength required is 400 N, and the minimum peel strength (for bonded layers) is 60 N/m (Table 1).

How should GCLs be stored on-site?

They should be stored in their original, intact wrapping, elevated off the ground, and protected from precipitation, heat, and UV exposure (Clause 8.2 implies protection through packing).

IS 14066

: 1994

Geosynthetic Clay Liners (GCL) - Specification

CurrentSpecializedSpecificationBIMGeotechnical · Geosynthetics and Ground Improvement

Archive.org BIS Portal Google

This standard specifies the requirements for geosynthetic clay liners (GCLs), which are factory-manufactured hydraulic barriers. It covers the materials, physical properties, performance criteria, test methods, and marking for GCLs used in environmental containment applications like landfills and ponds.

Specifies requirements for Geosynthetic Clay Liners (GCLs) for use in various containment applications.

Quick Reference Values

Maximum hydraulic conductivity5 x 10⁻¹¹ m/s

Minimum mass per unit area of bentonite3.66 kg/m²

Minimum swell index of bentonite24 ml/2 g

Minimum grab tensile strength400 N

Minimum peel strength (for needle-punched GCLs)60 N/m

Minimum overlap for panels150 mm

Practical Notes

Ensure GCLs are not deployed in rainy conditions to prevent premature hydration and swelling, which can make handling and seaming difficult.

Proper anchoring and backfilling is crucial, as GCLs have low interface friction angles, especially when hydrated, which can lead to slope stability issues if not accounted for in design.

Field seams are a critical point of potential leakage. Use a bead of granular bentonite along the overlap (typically 150-300mm) to ensure a robust hydraulic seal.