Geotextiles in Embankment Dams - Association of State Dam Safety ...

Geotextiles in Embankment Dams3.14 Illustration of geotextiles being used for filtration/separation beneath ripraperosion control revetments. ....................................................................................... 693.15 Additional examples of geotextiles used in protection, separation, anderosion control in embankment dams. .................................................................... 704.1 Illustration showing the concepts of soil piping and clogging a geotextile. ....... 744.2 Illustration showing the progressive steps leading to blinding of a geotextilewhich is a type of clogging that can be caused by using drainage aggregatewhich is too large in size. ........................................................................................... 774.3 Illustration showing examples of geotextile failures in soft foundations. ........... 834.4 Geotextile rupture limits due to cracking at various burial depths. Typicalvalues were used for geotextile strengths. ............................................................... 864.5 Photograph of a geotextile with a herbicide delivery system designed to stoproot penetration. .......................................................................................................... 876.1 Photograph of a truck delivering geotextile rolls to a construction site. Thetie down straps at the front of the truck are intruding into and have distortedthe shape of the top roll. This roll must be carefully examined to verify that ithas not been damaged during transport. ............................................................... 1186.2 Photograph showing proper offloading of geotextile product rolls. Clothslings rather than the forks of the lift are used to properly unload thisdelivery. ....................................................................................................................... 1186.3 Photograph of geotextile storage. A layer of fine-grained soil was placed inthe storage area to avoid placing the rolls directly on the rocky soil which isvisible in the left side of the photograph. Damage to the ends of theprotective wrappers is evident, the inspector required these rolls to be coveredby a tarp to prevent contamination by dust and to avoid degradation fromprolonged UV exposure. .......................................................................................... 1196.4 Photograph showing compaction equipment preparing a suitably smoothand firm subgrade surface for geotextile placement. ........................................... 1216.5 Photograph showing a defect in a prepared subgrade surface. This portionof the subgrade was rejected by the inspector and had to be filled andsmoothed. ................................................................................................................... 1216.6 Photograph showing moving a geosynthetic roll with a pipe and spreaderbar, and a spotter. The spotter (person walking in front of the equipment) isneeded to insure that the geosynthetic product does not strike any otherobjects which could damage the material. ............................................................. 1226.7 Photograph of a steel pipe and slings being used to move a geosynthetic rollacross a construction site to the installation area. ................................................ 1236.8 Photograph showing preparations for geosynthetic installation. A swale isused to divide a long slope and provide an intermediate anchor trenchlocation. Note the presence of proper equipment, sufficient labor, andadequate amounts of sand bags so materials can be efficiently installed andsecured. ....................................................................................................................... 1246.9 Photograph showing a haul road where the cover layer has been temporallyincreased to 5 feet to protect the geotextile from heavy equipment loading. .. 127xiv