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]
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ASTM Standards December Update
This month there are a number of changes to standards relating to masonry units, bricks, dimension stone, etc. There are also some changes to a few standards related to asphalt paving, and groundwater testing. ASTM D6453 – Standard Guide for Format of Computerized Exchange of Soil and Rock Test Data was withdrawn. Read on for the full list.

The Curious Case of No. 57 Stone
The American Society for Testing and Materials, or ASTM, No. 57 stone is often used as sub base fill material below road surfaces and buildings. It is a fragmented stone with angular edges and is regularly utilized as a drainage layer when used with geotextile fabric. Although the material is touted by many as "self-compacting," excess voids left from zero compactive effort in locations with little confinement may not eliminate the possibility of future settlement. What happens when the environment above the No. 57 stone causes it to settle?
[Editor] Read on for the answer to this interesting question in the case of settlement of a structure at the University of North Carolina at Chapel Hill. The contributed article by Katherine Witt describes how URETEK Mid-Atlantic used their high-density polyurethane resin to stabilize the No. 57 stone beneath a settled foundation as well as lift the surrounding slab back into place. [/Editor]

ASTM Updates January 2009
This month there is a new standard related to nondestructive testing, revisions for several standards involving aggregates, cements and mortars, and the standard test method for expansion index of soils. Click through for the list.