GB/T 17642-2025 Geosynthetics—Geocomposites made of geononwoven and geomembrance Geosynthetics—Geocomposites made of geononwoven and geomembrance
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ICS 59.080.70
CCS W 59
National Standard of the People's Republic of China
GB/T 17642-2025
Replaces GB/T 17642-2008
Geosynthetics - Geocomposites made of geononwoven and geomembrance
Issue date: 2025⁃04⁃25 Implementation date: 2025⁃11⁃01
Issued by the State Administration for Market Regulation of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Classification and code
5 Technical requirements
6 Text methods
7 Inspection rules
8 Packaging, storage and marking
Geosynthetics - Geocomposites made of geononwoven and geomembrance
1 Scope
This document specifies the product classification, specifications and codes, technical requirements, inspection rules, packaging, storage and marking of nonwoven composite geomembranes, and describes the test methods.
This document is applicable to nonwoven composite geomembranes which take nonwoven geotextiles as the base material and are compounded with membrane materials such as polyethylene (PE).
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3923.1 Textiles - Tensile properties of fabrics - Part 1: Determination of maximum force and elongation at maximum force using the strip method
GB/T 4666 Textiles - Fabrics - Determination of width and length
GB/T 6672 Plastics film and sheeting - Determination of thickness by mechanical scanning
GB/T 9345.1 Plastics - Determination of ash - Part 1: General methods
GB/T 13759 Geosynthetics - Terms and definitions
GB/T 13760 Geosynthetics - Sampling and preparation of test specimens
GB/T 13762 Geosynthetics - Test method for the determination of mass per unit area of geotextiles and geotextile - related products
GB/T 13763 Geosynthetics - Determination of trapezoid tearing force
GB/T 14800 Geosynthetics - Static puncture test (CBR test)
GB/T 15788 Geosynthetics - Wide - width tensile test
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 13759 and FZ/T 01153 and the following apply.
4 Classification and code
4.1 Product classification
Nonwoven composite geomembranes can be classified according to the following methods:
——By substrate material: polyester (PET), polypropylene (PP);
——By substrate process: staple fiber needle punched nonwoven geotextile (SN), filament spunbonded needle punched nonwoven geotextile (FN);
——By membrane material: composite geomembranes with materials such as polyethylene (PE), polyvinyl chloride (PVC);
——By the structure: composite geomembranes of one nonwoven and one geomembrane composite, two nonwovens and one geomembrane composite, one nonwoven and two geomembranes composite, two nonwovens and two geomembranes composite, etc.;
——By the composite process: thermal composite process, cast film composite process, etc.
4.2 Product specifications
4.2. 1 Staple fiber needle punched nonwoven composite geomembranes
The specifications of staple fiber needle punched nonwoven composite geomembranes are expressed by nominal strength. The nominal mass per unit area of finished products, nominal thickness and nominal width of the membrane materials are auxiliary specifications, which are designed according to the contract provisions and actual needs.
The recommended series of product specifications are as follows:
Nominal strength (kN/m): 5.0, 8.0, 10, 12, 14, 16, 18, 20, etc.
4.2. 2 Filament spunbond needle punched nonwoven composite geomembranes
The specifications of filament spunbonded needle punched nonwoven composite geomembranes are expressed by nominal strength. The nominal mass per unit area of finished products, nominal thickness and nominal width of the membrane materials are auxiliary specifications, which are designed in accordance with contract provisions and actual requirements.
The recommended series of product specifications are as follows:
Nominal strength (kN/m):12, 14, 16, 18, 20, 25, 30, 40, etc.
5 Technical Requirements
5.1 Material Quality
5.1.1 Products manufactured using thermal lamination process shall use polyethylene geomembranes that comply with GB/T17643. Other geomembrane materials shall also meet relevant standards.
5.1.2 The nonwoven geotextiles used in the products shall comply with GB/T17638 or GB/T17639 requirements.
5.2 Intrinsic Quality
5.2.1 General technical indicators for nonwoven composite geomembranes shall meet the requirements specified in Table 1. Composite geomembranes with staple fiber needle-punched nonwoven geotextiles shall additionally comply with Table 2 requirements, while those with filament spunbond needle-punched nonwoven geotextiles shall additionally meet Table 3 requirements.
Table 1 General Technical Requirements for Nonwoven Composite Geomembranes
The standard values for these optional items shall be specified in the supply contract.
5.2.2 The optional items include dynamic perforation (impact resistance), in-plane water flow, friction coefficient, UV resistance, oxidation resistance, creep performance, joint/seam strength, abrasion resistance, elongation under constant load, load at constant elongation, and elongation at break, as well as vertical permeability coefficient. The standard values for optional items shall be specified in the supply and demand contract
5.3 Appearance Quality
Appearance defects are classified as minor defects and major defects (as per Table 4). Major defects shall not be present on any product, while minor defects shall not exceed 5 per 200 meters.
Table 4 Classification of Appearance Defects
