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Line 4: − <li>Suitable apparent opening size (AOS) for non-woven fabrics, or percent open area (POA) for woven fabrics, to maintain water flow even with sediment and microbial film − build-up;</li> − + − + + + + + + + + + + + +
no edit summary
<p>Primary considerations are:
<p>Primary considerations are:
<ol>
<ol>
<li>Maximum forces that will be exerted on the fabric (i.e., what tensile, tear and puncture strength ratings are required?);</li>
<li>Maximum forces that will be exerted on the fabric (i.e., what tensile, tear and puncture strength ratings are required?);</li>
<li>Load bearing ratio of the underlying native soil (i.e., is geotextile needed to prevent downward migration of aggregate into the native soil?);</li>
<li>Load bearing ratio of the underlying native soil (i.e. is the geotextile needed to prevent downward migration of aggregate into the native soil?);</li>
<li>Texture (i.e., grain size distribution) of the overlying aggregate material; and</li>
<li>Texture (i.e., grain size distribution) of the overlying fill material; and</li>
<li>Permeability of the native soil</li>
<li>Permeability of the native soil</li>
<li>Suitable apparent opening size (AOS) for non-woven fabrics, or percent open area (POA) for woven fabrics, to maintain water flow even with sediment and microbial film build-up;</li>
</ol>
</ol>
<table class="table table-bordered">
<caption>Recommended criteria for selection of geotextile fabric</caption>
<tr class="success"><th>Percent media passing 0.075 mm (#200 sieve)</th><th>Non-woven fabric apparent opening size (AOS, mm)</th><th>Woven fabric percent open area (POA, %)</th><th>Permittivity (sec<sup>-1</sup>)</th></tr>
<tr><td align="center" valign="middle">>85</td><td align="center" valign="middle"rowspan = 2>≤ 0.3</td><td align="center" valign="middle">Not recommended</td><td align="center" valign="middle" rowspan = 2>0.1</td></tr>
<tr><td align="center" valign="middle">50 - 85</td><td align="center" valign="middle" rowspan = 3>≥ 4</td></tr>
<tr><td align="center" valign="middle">15 - 50</td><td align="center" valign="middle" rowspan = 3>≤ 0.6</td><td align="center" valign="middle">0.2</td></tr>
<tr><td align="center" valign="middle">5 - 15</td><td align="center" valign="middle" rowspan =2>0.5</td></tr>
<tr><td align="center" valign="middle">≤ 5</td><td align="center" valign="middle">≥ 10</td></tr>
</table>
</p>
</p>