<p><p><h2>Commentary</h2>To date, the incorporation of fibers into subgrade and/or subbase materials has been limited to laboratory and small trial projects.

<p><p><figure id='attachment_2577' style='max-width:435px' class='caption aligncenter'><img class="wp-image-2577 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Photograph of a soil mixer behind a tractor mixing fibers in a clay soil." width="435" height="285" /><figcaption class='caption-text'> Mixing of fibers with soil in field

<p><p><strong>Reference(s):</strong></p><p><em>Crockford et al. (1993)<br>Grogan (1994)</em></p><p><strong>Method Summary</strong></p><p>Proper compaction is an important part of fiber-reinforced soils. The optimum moisture content and the maximum dry density of the mix are determined using the standard or modified Proctor tests. The moisture content and the density during the construction are monitored.

<p><p><figure id='attachment_3431' style='max-width:627px' class='caption aligncenter'><img class="wp-image-3431 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Plan view of field tests conducted for fiber reinforcement in pavement systems at Texas Transportation Institute." width="627" height="684" /><figcaption class='caption-text&#039

Reference(s):
Ding and Hargrove (2006)
Michalowski and Zhao(1995a, b)
Michalowski and Zhao (1996)
Michalowski and Cermak (2003)
Sadek (2010)

<p><p><strong>Reference(s):</strong></p><p><em>Tingle et al. (2002)<br>Newman and White (2008)<br>Grogan (1994)</em></p><p><strong>Method Summary</strong></p><p>This method tests the improvement resulting from fiber reinforcement and chemical stabilization using a penetration test. The method can be adapted for a CPT or a DCP, but is better suited to a DCP test. An in-situ penetration tests can serve as either quality control or quality assurance.

<p><p><strong>Reference(s):<br></strong><em>Bhattacharya and Pandey (1984); Chandra (2008);<br>Consoli et al. (1998a); Consoli et al. (1998b);<br>Consoli et al. (2003); Crockford et al. (1993);<br>Kalantari and Huat (2008); Kaniraj and Havanagi (2001);<br>Khattak and Alrashidi (2006); Kumar et al. (2006);<br>Kumar et al. (2007); Kumar et al. (2008);<br>Li and Ding (2002); Liang (1992);<br>Medjo Eko and Riskowski (1994);<br>Newman and White (2008); Puppala and Mesunda (2000);<br>Rafalko et al.

<p><p><strong>Reference(s):</strong></p><p><em>Bhattacharya and Pandey (1984)<br>Liang (1992)<br>Crockford et al. (1993)<br>Medjo Eko and Riskowski (1994)<br>Consoli et al. (1998 b)<br>Puppala and mesunda (2000)<br>Kaniraj and Havanagi (2001)<br>Tingle et al. (2002)<br>Consoli et al. (2003)<br>Khattak and Alrashidi (2006)<br>Kumar et al. (2006)<br>Kumar et al. (2007)<br>Rafalko et al. (2007)<br>Tang et al. (2007)<br>Kalantari and Huat (2008)<br>Kumar et al.

<p><p><strong>Reference(s):</strong></p><p><em>Newman and White (2008)</em></p><p><strong>Method Summary</strong></p><p>The roller compactor employs an on-board computer to control compaction criteria and to record machine speed and coverage through GIS and GPS systems.

<p><p><strong>Reference(s):</strong></p><p><em>Consoli et al. (1998a)<br>Consoli et al. (2003)</em></p><p><strong>Method Summary</strong></p><p>The plate load test uses a steel bearing plate and a hydraulic jack to apply a known load then measure the resulting surface deflection. Comparing the load-settlement curves before and after the fiber reinforcement, an improvement factor can be defined.