1710 – GEOSYNTHETICS
1700-17 Section 1710
GEOSYNTHETICS 1710.1 DESCRIPTION This specification covers the requirements for paving fabrics and geosynthetics and securing pins installed for subsurface drainage, separation, base course reinforc ement and subgrade stabilization. This also covers the requirements for separation geotextile for erosion control. 1710.2 REQUIREMENTS
a.General.
1.Compose all geosynthetics of at least 85% by weight polyolefins or polyesters.
2.Use geosynthetics resistant to chemical attack, mildew and rot.
3.Package in protective wrapping , store, handle and identify all geosynthetics according to ASTM D 4873.
4.Do not use torn or punctured geosynthetics.
5.Woven geotextiles with slit-tape or slit-film fila ments in both the machine direction (MD or warp) and the cross-machine direction (CD, weft or fill) are prohibited.
6.When seams are required for geotextiles, use "Butterfly" seams that have a Federal Standard designation of Type SSD-1. Place the s titching approximately 1 inch from the fo ld. Make sure the two fabric edges are even and have been completely penetrated by the se am. Use polyester, polypropylene or Kevlar thread with durability equal to or great than the material used in the fabric. Seam strength requirements shall be as specified in the Contract Documents.
b.Securing Pins. When required, provide steel securing pins that are nominally 1/4 inch diameter, 18 inches long, pointed at one end and fitted with a 1-1/2inch outside diameter steel washer at the other end.
c.Paving Fabric. Provide a nonwoven geotextile that complies with the general physical and the geotextile property requirements for an AASHTO M 288 paving fabric unless otherwise specified in the Contract Documents. Use a paving grade asphalt recommended by the manufacturer and conforming to the provisions in the AASHTO M 288 Appendix Section 1.6, unless otherwise specified in the Contract Documents, to saturate the paving fabric, as well as bond it to the existing pavement.
d.Subsurface Drainage. Provide a woven or nonwoven geotextile that complies with the general physical and the geotextile property requirements for an AASHTO M 288, Class 2, subsurface drainage geotextile unless otherwise specified in the Contract Documents.
e.Separation Geotextile. Provide a woven or nonwoven geotextile that complies with the general physical and the geotextile property requirements for an AASHTO M 288, Class 2, separation geotextile unless otherwise specified in the Contract Documents. See subsection 1710.2a.(5) regarding the use of slit-tape geotextiles.
f.Base Course Reinforcement. Provide a single-layer geogrid or woven geotextile that complies with the properties in TABLE 1710-1 for reinforcement of an aggregate base course. MD: Machine Direction, CD: Cross- machine Direction. 1710 – GEOSYNTHETICS
1700-18 Table 1710-1: Base Course Reinforcement Ge Osynthetic Mimimum Averge Roll Values
Property Test Method Requirements Tensile Strength (at 5% strain) ASTM D 4595 580 lb/ft MD 900 lb/ft CD Tensile Strength (at 2% strain) ASTM D 4595 280 lb/ft MD 450 lb/ft CD Coefficient of Soil Interaction GRI-GT6/GG5 0.8 Junction Strength (geogrid) GRI:GG2 25 lbs Permittivity (geotextile) ASTM D 4491 0.40 sec-1 Apparent Opening Size* (geotextile) ASTM D 4751 30 U.S. Sieve (0.0232 inches) Aperture Stability (geogrid) ** Minimum of 0.32 m-N/Deg (MD direction) * ASTM D 4751: AOS IS A MAXIMUM OPENING DIAMETER VALUE ** The Aperture Stability is based on resist ance to in-plane rotational movement m easured by applying a 20 kg-cm (2 m-N) moment to the central junction of a 9 inch by 9 inch specimen restrained at its perimeter in accordance with U.S. Army Corps of Engineers Methodology for measurement of Torsional Rigidity. The coefficient of interaction is ba sed on the soil being a granular, non-cohesive material with less than 10% fines. If these base soils are not available, perform a site specific design and increase the base course thickness, accordingly.
g.Subgrade Stabilization. Provide a woven geotextile, geogrid or geogrid/geotextile combination, as specified in the Contract Document s, for subgrade stabilization that complies with the properties in TABLE 1710-2 . This table is only applicable for subgrades with CBR values greater than 1. For subgrades with CBR values less than 1, a site specific design will be required. TABLE 1710-2: SUBGRADE STABILIZATION GEOSYNTHETIC MIMIMUM AVERGE ROLL VALUES Property Test Method Requirements Tensile Strength (at 5% strain) ASTM D4595 810 lb/ft MD 1340 lb/ft CD Tensile Strength (at 2% strain) ASTM D4595 410 lb/ft MD 620 lb/ft CD Coefficient of Soil Interaction GRI-GT6/GG5 0.8 Junction Strength (geogrid) GRI:GG2 25 lbs Permittivity (geotextile) ASTM D4491 0.40 sec-1 Apparent Opening Sizea (geotextile) ASTM D4751 30 U.S. Sieve (0.0232 inches) aASTM D 4751: AOS is a Maximum Opening Diameter Value
h.Pavement Waterproofing Membrane. Provide an asphalt saturated paving fabric coated with a rubberized asphalt adhesive that complies with the properties in TABLE 1710-3 . TABLE 1710-3: PAVEMENT WATERPROOFING ME MBRANE MIMIMUM AVE RGE ROLL VALUES Property Test Method Requirements Permeance-Perms ASTM E 96 Method B 0.10 perms (max) Pliability (180° bend on a 1/4” mandrel @ -25°F) ASTM D 146 No cracking in fabric or rubber Puncture Resistance ASTM E 154 200 lbs Tensile Strength ASTM D 882 50 lbs/in If required, provide a material for a prime coat (comprised of refined asphalt and a rapidly drying solvent) that complies with the requirements of DIVISION 1200. 1710.3 TEST METHODS Test geosynthetic materials according to the ASTM test methods cited in subsection 1710.2 . 1710.4 PREQUALIFICATION
a.All material provided under this specification must be prequalified through the Engineer of Tests.
Source: Kansas Standard Specifications for State Road and Bridge Construction, 2015 Edition. Pages 807–808 of 978.