TEXTILES.ORG
During 2016, representatives of ASTM International and the ASTM D35 Committee on Geosynthetics were in discussion with the American Association of State Highway and Transportation Officials’ (AASHTO) Subcommittee on Materials (SOM), Technical Section 4e (TS 4E), regarding their current revision efforts on Standard Specification for Highway Applications, AASHTO M288.
TS 4e includes 26 state DOT representatives from their respective Departments of Materials and Tests, plus six AASHTO representatives. SOM is continuously seeking input from various organizations to improve M288 and expand its scope to include other highway product applications. The scope of the current standard states: “This is a materials specification covering geotextile fabrics for use in subsurface drainage, separation, stabilization, erosion control, temporary silt fence, and paving fabrics.”
During the February 1–3, 2017, ASTM meeting in Norfolk, Va., ASTM D35 Committee on Geosynthetics held a well-attended one-hour meeting to discuss coordination of effort between TS 4e and the ASTM D35 committee. After an extensive discussion among attendees on this issue and acknowledgment that the ASTM D35 committee has already published some geosynthetic material specifications,
an informal show of hands approved the D35 Committee continuing to develop applicable “consensus” product specifications for the geosynthetics community. Based on the comments from the meeting, and in an effort to focus their efforts with regard to geosynthetic specification development, the ASTM D35 Executive Committee voted to form a new Subcommittee, ASTM D35.06 on product specifications.
The first meeting of ASTM D35.06, Subcommittee on Product Specifications, is scheduled for the next ASTM D35 committee meetings in Toronto, Ont., Canada, June 14–16, 2017. The first meeting will include an ASTM D35 Workshop on Product Specifications, 8 a.m.–12 noon on Wednesday, June 14. Further details about the Subcommittee D35.06 meeting schedule will be forthcoming and published prior to the Toronto meeting.
Report from the ASTM D35 Committee on Geosynthetics, February 2017
The ASTM D35 Committee on Geosynthetics met in Norfolk, Va., February 1–3, 2017. Among the topics addressed were these three subcommittee reports.
Under ASTM D35.01, Subcommittee on Mechanical Properties, a task group is working to develop a protocol for biaxial testing of geosynthetics. This test would describe the tensile properties of the geosynthetic as it is pulled simultaneously in two directions. It is hoped information from this test will be used in a model to design geosynthetic-reinforced pavements. For more information, contact Eli Cuelho,
elic@montana.edu.
ASTM D35.04, Subcommittee on Geosynthetic Clay Liners, is embarking on an effort to develop a standard guide for polymer-amended bentonites. Several volunteer laboratories will conduct tests on amended bentonites to see if the same tests used for standard bentonites will be valid or if a new set of tests will need to be developed. In addition, a new guide for installation damage of GCLs is being developed. Further a round robin is in progress to improve the Fluid Loss Test ASTM D5891. Comments on the recent ballot on the Free Swell Test ASTM D5890 were discussed and changes were made. The standard will be reballotted.
ASTM D35.05, Subcommittee on Geosynthetics in Erosion and Sediment Control, continues to spend significant time enhancing basic index test methods for rolled erosion control products (RECPs). Recently, thickness, mass per area, and tensile strength have been approved with important clarifications, as have compression, resiliency, and stiffness. One index test method, light penetration, is requiring a much greater refinement effort as it has been found that the method works better for some product types than for others. Some new standards are under development in the subcommittee. A flexural strength test method has been developed for a new class of materials—geosynthetic cementitious composite mats (GCCMs)—that are used for channel linings; a new tensile strength test is under development for ground anchors used with turf reinforcement mats; and a new specification for turf reinforcement mats has been introduced.
For more information:
Katerina Koperna—ASTM D35
Committee, staff representative, kkoperna@astm.org
Jim Goddard—ASTM D35
Committee chairman, jimgoddard3@gmail.com