Geosynthetics - Geotechnical Investigation and Design Tables - page 204

Table 16.2 Basic materials (Van Santvoort, 1995).

Material Symbol Unit mass Tensile strength Modulus of Strain at break

(kg/m 3 ) at 20 ◦ C (N/mm 2 ) elasticity (N/mm 2 ) (%)

Polyester PET 1380 800-1200 12000-18000 8-15

Polypropylene PP 900 400-600 2000-5000 10-40

Polyethylene PE 920 80-250 200-1200 20-80

•

High density HDPE 950 350-600 600-6000 10-45

Low density LDPE 920 80-250 200-1200 20-80

•

Polyamide PA 1140 700-900 3000-4000 15-30

Polyvinylchloride PVC 1250 20-50 10-100 50-150

•

For higher loads and for critical structures PP loses its effectiveness due to its
poor creep properties under long term and sustained loads. PET is usual in such
applications.

16.3 Geosynthetic functions
•

The geosynthetic usually fulfils a main function shown in the table below, but
often a minor function as well.

Table 16.3 Functional applications.

Material Application

Reinforcement/Filter Drainage Screen Properties

Geotextile Geogrid Geonet Geomembrane High Low

PET X X Strength Creep

modulus resistance to

cost, Unit weight alkalis

PP X X Creep Cost, Unit

resistance to weight,

alkalis Resistance to

fuel

PE X X (PE) Strain at (PE) Unit

- HDPE X X failure creep, weight,

- MDPE X resistance Strength,

- LDPE to alkalis Modulus, Cost

- CSPE X

- CPE X

PA X Resistance

to alkalis and
detergents

PVC X Strain at failure, Strength,

Unit weight modulus