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)
The Countywide Recycling & Disposal Facilities in Stark County, Ohio have a new round of problems. There has been much debate over an underground fire reportedly caused by the disposal of aluminum dross waste, a byproduct of aluminum production, dumped between 1993 and 2001. The site has long received complaints for odors and for a long time denied that there was a fire. They have also had problems with slope stability, including a failure of a portion of the south slope in 2006, possibly a result of the destabilizing effect of the fire. Early this year the Ohio EPA cited the facility for violating 8 environmental regulations after waste was found to have migrated outside the permited waste area.
Their latest problems involve a tear or leak of a geosynthetic lining that caps the facility to control gas and odors from the underground fires and regular landfill gas. The leak resulted in 500 to 5,000 gallons of leachate spilling into a sediment pond. The material fortunately did not leave the site and was pumped out of the pond and transfered to a treatment plant where their leachate usually goes. The landfill, one of the largest in Ohio, handles about 6,000 tons of trash a day, including about half of Summit County’s residential garbage.
Standards governing the testing of tensile strength of geogrid and geotextile tensile strength are among the standards updated over the past month by the ASTM. This includes a new standard for "Determining Small-Strain Tensile Properties of Geogrids and Geotextiles by In-Air Cyclic Tension Tests". A number of standards relating to concrete including capping of concrete cyllinders for testing have also been updated. Click through for the list.