GEOTEXTILES IN EARTH REINFORCEMENT

After briefly surveying the use of geotextiles in earth reinforcement the author refers to the Colorado Division of Highways fabric wall test section near Glenwood Springs. This was constructed in 1982 and consists of a 300 ft continuous wall divided into 10 segments. Each segment is 30 ft wide and 16 ft high and is constructed with granular backfill reinforced with a different style or weight of nonwoven fabric. Two segments were purposely underdesigned but did not fail, even when loaded with 17 ft of fill. No creep related movement had been observed in any segment after 2 years. Two other retaining walls in Colorado are briefly described. One timber-faced reinforced earth wall uses a facing-forming system of railroad ties and Mirafi 500 X fabric. Costs are discussed. The design procedure for geotextile retaining walls used, which was drawn up by the US Forest Service, is reproduced. (TRRL)