Geotextiles are frequently used for subgrade improvement under roadways. Caltrans has released a document titled "Guide for Designing Subgrade Enhancing Geotextiles". This 18-page document covers what situations can be improved using geotextiles and includes a flowchart for guidance on when to apply them and for what purposes. From Geosynthetics magazine. (Image by Caltrans)
This post contains a list of new, revised and otherwise updated ASTM standards that pertain to the geotechnical engineering, materials testing and related fields. Standard C39/C39M for testing the compressive strength of concrete cyllinders was updated, as was C42/42m for obtaining and testing drilled cores and sawed beams of concrete. The month of March also saw several geosynthetic standards being updated or added, including new standards for selecting the test method for geomembrane seams, and for testing the flexural rigidity of geogrids and other geosynthetics. There are also a few updated standards related to asphalt mix design and sampling of asphalt. Click through for updated ASTM Standards relating to geoprofessionals.