Creating MnDOT specifications for geotextile under riprap.
Link to this table
| Geotextile Properties for Use Under Riprap |
| Geotextile Property |
Test Method (ASTM) and Units |
Type 3 (under Class I and Class II random riprap) (a) |
Type 4 (under Class III and Class IV random riprap and hand-placed riprap, slopes up to 3:1) (a) |
Type 7 (under Class III and Class IV random riprap, slopes > 3:1) (a)(b) |
| B1 Grab Tensile Strength minimum, each principal direction |
D4632 lb |
100 |
200 |
300 |
| B2 Elongation minimum, each principal direction |
D4632 percent |
50 |
50 |
50 |
| B3 Seam Breaking Strength minimum (c) |
D4632 lb |
90 |
180 |
270 |
| B4 Apparent Opening Size (AOS) maximum (d) |
D4751 U.S. Std. sieve size |
50 |
50 |
50 |
| B5 Permittivity minimum (e) |
D4491 falling head sec−1 |
0.5 |
0.5 |
0.5 |
