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G <br />r <br />(~" <br />fi ~ ~..~ <br />-:~ <br />.~_` -'~ <br />- ~} ~ <br />i <br />~~~. <br />;~ ~~ ~j <br />.1L_ , <br />I / <br />Enkamat applications can be summarized into two basic ca[egories- <br />Slope Protection and Channel Lining. Employing Enkamat into the design <br />allows a "Green Engineering" alternative to hard armor (rip-rap or paved <br />linings). Enkamat combined with the proper vegetation results in an <br />attractive alternative with long term performance. <br />Erosion Resistance of Grass <br />Rein/orced and Plain <br />xo <br />is <br />~ 16 <br />\ 16 <br />r 12 <br />- 10 <br />0 <br />8 <br />~ 6 <br />u <br />d <br />f Z <br />0 <br />Channel Design <br />The wide variety of potential channel <br />geometry, geotechnicat, climatic and <br />hydraulic parameters should all be <br />considered when designing for <br />"Grassed Lined" erosion controlsys- <br />tems. Two widely accepted design <br />methodologies exist and are noted <br />below. These methods allow the <br />designer to perform permissible veloo- <br />ity or permissible tractive Force (shear) <br />designs to determine the suitability of <br />the lining material. <br />-. The permissible velocities and shear <br />I' ~ stresses for Enkamat have been <br />i "\ <br />determined through testing and <br />- ~ ~ research conducted at recognized <br />laboratories and are summarized in <br />graphs I & II on page 5. <br />Enkamat Requvement Cwde <br />10 <br />r 5 I ~ <br />Enkamat Required <br />E 3 ' I <br />2 <br />1 I <br />0.5 ~ <br />3` 0.3 i <br />0.7 I <br />~ 37.8 <br /> ( <br /> I <br /> <br /> <br />I <br />q.3 <br />0.003 0.03 0.3 3 <br />AVERPGE PHRiIQE SIEf (mm) <br />CLAV SILT $PNO <br />a <br />x <br />If the permissible velocity and/or per- <br />missible shear stress are greater than <br />the computed number [he design is <br />considered acceptable. <br />Manning's Equation is commonly used <br />for evaluating channel flow: <br />Q = (1.49/n) (A) (R~r') (5'n) <br />where: <br />Q =discharge <br />n = Manning's roughness coefficien[* <br />A =cross-sectional area <br />5 =channel bed slope <br />R =hydraulic radius = A/P, where <br />P=wetted perimeter <br />'For Enkamat, Manning's roughness coefficient, n=0.03 <br />can be used. (ARual values tan be provided upon request) <br />For the Permissible Velocity Approach <br />the area of flow can be calculated and <br />used to compute the flow velocity using <br />the following equation. <br />( <br />I <br />t <br />Na Enkamat Required <br />30 <br />GPPVEL <br />36.4 <br />i 9.8 0 <br />65 <br />3.3 ° <br />1 p <br />' 1.6 W <br />0.9 3 <br />O.J <br />I 0.3 <br />Iaa <br /> <br />~' <br />DURATION OF rLOW (HOURS) xorr: oaw oem;neepom aaia RrPOer us <br />