A 2004 paper by J.P. Giroud and Jie Han provides a practical design method for geosynthetic-reinforced unpaved roads. The method outlined in the paper was very detailed, and the authors wanted to provide a summary for the benefit of practitioners who wish to use the method. Additionally, some equations in the paper are generic and some have been calibrated for specific geosynthetics (the Tensar BX1100 and BX1200 biaxial geogrids, with new work by another author applying to Tensar’s Triax geogrid) and some practitioners were not clear on this matter. Finally, the authors stress the need for calibration of the method when using other geosynthetics. These three issues were addressed by a 2-part series in Geosynthetics Magazine by Giroud and Han. You can read the first part and the second part at GeosyntheticsMagazine.com. [Image from Geosynthetics Magazine]
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Continuing Problems for Ohio Landfill
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.
Story by way of Geosynthetica. Image from Long Live the Village Green.
ASTM Updates August 2009
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.