Two new standards from the Geosynthetics committee of ASTM will help define properties that can be used in the design of geosynthetic reinforced pavement. I know in my practice in Arizona, ADOT simply allows a boost of Resilient Modulus (R-Value) of 10 when biaxial geogrids are used. Perhaps in time this will lead to a design method to account for the geosynthetic reinforcement in a more analytical way. [Source: Geosynthetics Magazine]
In this month’s ASTM updates, there is a new standard for determining the laboratory density of soil specimens. Not having a standard for this item was a common problem for us in our practice. The lab would give us a density on ring samples by weiging, drying and weighing again using the known volume of the rings, but there was never any standard to go with it. Other updates this month include ones related to dimension stone, fiber reinforced concrete, sulfate content of soils, and calcium and magnesium content of water.
Another busy month for ASTM with 66 new, revised or otherwise updated standards related to geotechnical and geological engineering (although not as busy as last month). A couple that caught my eye include brand new standards for geospatial data requirements related to abandoned mines, a new standard for sampling of EPS or geofoam, updated standards for mortar and cement, flexural strength of concrete, LA Abrasion test for aggregates, acceptance testing of geosynthetic clay liners, electrical methods for leak detection of geomembranes with earth cover and classification of soils and soil-aggregate mixtures for highway construction purpose (AASHTO classification).
Those involved in the materials testing side of the business should take a close look at the full list as there are also a number of updated standards relating to various asphalt and and aggregate tests, capping of concrete cyllinders and other related testing standards.
For my practice, perhaps the most significant standard that was updated was D 2488 – Standard Practice for Description and Identification of Soils (Visual-Manual Procedure) which we rely on for our field USCS classifications. I’ll be curious to see what those changes entail. Click through for the full list.