https://epg.modot.org/index.php?title=Category:628_High_Friction_Surface_Treatment&feed=atom&action=historyCategory:628 High Friction Surface Treatment - Revision history2024-03-28T16:25:25ZRevision history for this page on the wikiMediaWiki 1.33.1https://epg.modot.org/index.php?title=Category:628_High_Friction_Surface_Treatment&diff=50357&oldid=prevSmithk: Updated website links (for increased security)2021-10-22T17:52:19Z<p>Updated website links (for increased security)</p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 17:52, 22 October 2021</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l27" >Line 27:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Curves'''</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Curves'''</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The following table is from [http://d2dtl5nnlpfr0r.cloudfront.net/tti.tamu.edu/documents/TTI-2012-8.pdf ''Using High Friction Surface Treatments to Improve Safety at Horizontal Curves''], a July 2012 Texas A&M Transportation Institute report. It provides guidance on the location to begin placement in advance of the [<del class="diffchange diffchange-inline">http</del>://epg.modot.<del class="diffchange diffchange-inline">mo.gov</del>/index.php?title=905.1_Traffic_Data_Collection#905.1.2.6_Measuring_Degree_of_Curvature PC] of a curve. The approach speed should be the operating speed as determined by a field analysis, and the curve speed is the posted advisory speed. Engineering judgment and field evaluation should be used to determine the beginning and the length of the treatment. The HFST can often be ended at the [<del class="diffchange diffchange-inline">http</del>://epg.modot.<del class="diffchange diffchange-inline">mo.gov</del>/index.php?title=905.1_Traffic_Data_Collection#905.1.2.6_Measuring_Degree_of_Curvature PT].</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The following table is from [http://d2dtl5nnlpfr0r.cloudfront.net/tti.tamu.edu/documents/TTI-2012-8.pdf ''Using High Friction Surface Treatments to Improve Safety at Horizontal Curves''], a July 2012 Texas A&M Transportation Institute report. It provides guidance on the location to begin placement in advance of the [<ins class="diffchange diffchange-inline">https</ins>://epg.modot.<ins class="diffchange diffchange-inline">org</ins>/index.php?title=905.1_Traffic_Data_Collection#905.1.2.6_Measuring_Degree_of_Curvature PC] of a curve. The approach speed should be the operating speed as determined by a field analysis, and the curve speed is the posted advisory speed. Engineering judgment and field evaluation should be used to determine the beginning and the length of the treatment. The HFST can often be ended at the [<ins class="diffchange diffchange-inline">https</ins>://epg.modot.<ins class="diffchange diffchange-inline">org</ins>/index.php?title=905.1_Traffic_Data_Collection#905.1.2.6_Measuring_Degree_of_Curvature PT].</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><center></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><center></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Intersections'''</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Intersections'''</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Stopping sight distance can be used to determine the length of the HFST prior to an intersection. However, if frequent back-ups occur, it might be necessary to increase the length of the HFST upstream of the intersection. [<del class="diffchange diffchange-inline">http</del>://epg.modot.<del class="diffchange diffchange-inline">mo.gov</del>/index.php?title=230.2_Vertical_Alignment#230.2.5_Stopping_Sight_Distance_and_K_Factors EPG 230.2.5 Stopping Sight Distance and K Factors] provides guidance on stopping sight distance.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Stopping sight distance can be used to determine the length of the HFST prior to an intersection. However, if frequent back-ups occur, it might be necessary to increase the length of the HFST upstream of the intersection. [<ins class="diffchange diffchange-inline">https</ins>://epg.modot.<ins class="diffchange diffchange-inline">org</ins>/index.php?title=230.2_Vertical_Alignment#230.2.5_Stopping_Sight_Distance_and_K_Factors EPG 230.2.5 Stopping Sight Distance and K Factors] provides guidance on stopping sight distance.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Grades'''</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Grades'''</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[image:HFST.jpg|right|550px]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[image:HFST.jpg|right|550px]]</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>[<del class="diffchange diffchange-inline">http</del>://epg.modot.<del class="diffchange diffchange-inline">mo.gov</del>/files/5/5b/Green_Book_Table_3-36.pdf Table 3-36] (involves grade), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>[<ins class="diffchange diffchange-inline">https</ins>://epg.modot.<ins class="diffchange diffchange-inline">org</ins>/files/5/5b/Green_Book_Table_3-36.pdf Table 3-36] (involves grade), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>[<del class="diffchange diffchange-inline">http</del>://epg.modot.<del class="diffchange diffchange-inline">mo.gov</del>/files/b/b7/Green_Book_Table_3-34.pdf Table 3-34] (no grade change), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>[<ins class="diffchange diffchange-inline">https</ins>://epg.modot.<ins class="diffchange diffchange-inline">org</ins>/files/b/b7/Green_Book_Table_3-34.pdf Table 3-34] (no grade change), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td></tr>
</table>Smithkhttps://epg.modot.org/index.php?title=Category:628_High_Friction_Surface_Treatment&diff=49905&oldid=prevSmithk: /* Placement of HFST */2021-08-17T20:21:43Z<p><span dir="auto"><span class="autocomment">Placement of HFST</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 20:21, 17 August 2021</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l24" >Line 24:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Placement of HFST==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Placement of HFST==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">[[image:HFST.jpg|right|550px]]</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Curves'''</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Curves'''</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Grades'''</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>'''Grades'''</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[image:HFST.jpg|right|550px]]</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[http://epg.modot.mo.gov/files/5/5b/Green_Book_Table_3-36.pdf Table 3-36] (involves grade), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[http://epg.modot.mo.gov/files/5/5b/Green_Book_Table_3-36.pdf Table 3-36] (involves grade), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[http://epg.modot.mo.gov/files/b/b7/Green_Book_Table_3-34.pdf Table 3-34] (no grade change), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[http://epg.modot.mo.gov/files/b/b7/Green_Book_Table_3-34.pdf Table 3-34] (no grade change), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div></td></tr>
</table>Smithkhttps://epg.modot.org/index.php?title=Category:628_High_Friction_Surface_Treatment&diff=49903&oldid=prevSmithk at 20:20, 17 August 20212021-08-17T20:20:06Z<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 20:20, 17 August 2021</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>High Friction Surface Treatments place a thin layer of specially engineered, durable, high friction aggregates as a topping on a thermosetting polymer resin binder – usually polymeric, modified polyester, or urethane. These aggregate systems have a long lasting skid resistance and also make the overlay much more resistant to wear and polishing. The resin or polymer binder combination locks the aggregate firmly in place, creating an extremely rough, hard, durable surface capable of withstanding everyday roadway demands such as heavy braking and even snowplowing. HFST restores pavement surface friction characteristics where traffic has worn down existing pavement surface aggregates. HFST can also help compensate for inadequate geometric designs such as sharp curves and/or substandard or variable superelevations. Refer to [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/pdfs/fhwa-cai-14-019_faqs_hfst_mar2014_508.pdf FHWA's HFST FAQs website]. </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>High Friction Surface Treatments place a thin layer of specially engineered, durable, high friction aggregates as a topping on a thermosetting polymer resin binder – usually polymeric, modified polyester, or urethane. These aggregate systems have a long lasting skid resistance and also make the overlay much more resistant to wear and polishing. The resin or polymer binder combination locks the aggregate firmly in place, creating an extremely rough, hard, durable surface capable of withstanding everyday roadway demands such as heavy braking and even snowplowing. HFST restores pavement surface friction characteristics where traffic has worn down existing pavement surface aggregates. HFST can also help compensate for inadequate geometric designs such as sharp curves and/or substandard or variable superelevations. Refer to [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/pdfs/fhwa-cai-14-019_faqs_hfst_mar2014_508.pdf FHWA's HFST FAQs website]. </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[image:628 HFST.jpg|right|400px|thumb|<center>'''Blower used to place aggregate onto fresh epoxy for HFST surface'''</center>]]</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Missouri’s first HFST was placed on US 54 in Jefferson City in the fall of 2013. This location had a history of wet weather crashes. Several low to mid-cost safety improvements were tried, but over time were not able to alleviate all wet weather incidents. This project and three others in the Central District were paid by a [http://www.fhwa.dot.gov/hfl/ Highways for Life] grant. Due to the success of these projects, Missouri applied for and received federal funding to install HFST in every district through the [http://www.fhwa.dot.gov/accelerating/grants/ Accelerating Innovation Deployment (AID)] grant.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Missouri’s first HFST was placed on US 54 in Jefferson City in the fall of 2013. This location had a history of wet weather crashes. Several low to mid-cost safety improvements were tried, but over time were not able to alleviate all wet weather incidents. This project and three others in the Central District were paid by a [http://www.fhwa.dot.gov/hfl/ Highways for Life] grant. Due to the success of these projects, Missouri applied for and received federal funding to install HFST in every district through the [http://www.fhwa.dot.gov/accelerating/grants/ Accelerating Innovation Deployment (AID)] grant.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
</table>Smithkhttps://epg.modot.org/index.php?title=Category:628_High_Friction_Surface_Treatment&diff=35196&oldid=prevSmithk: HFST cost-effectively increases the safety of road segments where vehicles frequently depart the traveled way due to polishing of the existing pavem't aggregate or by slightly substandard geometry2015-02-25T18:47:03Z<p>HFST cost-effectively increases the safety of road segments where vehicles frequently depart the traveled way due to polishing of the existing pavem't aggregate or by slightly substandard geometry</p>
<p><b>New page</b></p><div>{|style="padding: 0.3em; margin-left:10px; border:2px solid #a9a9a9; text-align:left; font-size: 95%; background:#f5f5f5" width="410px" align="right" <br />
|-<br />
|align="center" | '''Additional Information'''<br />
|-<br />
|* [https://s3.amazonaws.com/media.atssa.com/default-file/1480+ATSSA+High+Friction+LoRes.pdf ATSSA], a nonstandard Job Special Provision for HFST <br />
|-<br />
|* [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/friction.cfm Every Day Counts (EDC) 2012 Initiatives]<br />
|-<br />
|* [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/pdfs/fhwa-cai-14-019_faqs_hfst_mar2014_508.pdf FHWA's HFST FAQs]<br />
|-<br />
|* [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/pdfs/hfst_brochure.pdf FHWA Brochure]<br />
|-<br />
|* [http://d2dtl5nnlpfr0r.cloudfront.net/tti.tamu.edu/documents/TTI-2012-8.pdf ''Using High Friction Surface Treatments to Improve Safety at Horizontal Curves''], a Texas A&M Transportation Institute (TTI) report<br />
|-<br />
|* [[media:628 HFST demonstration.docx|Accelerating Innovation Deployment (AID) Application]]<br />
|}<br />
High Friction Surface Treatments (HFST) can improve wet crash locations as well as locations that would benefit from increases in friction due to polishing or the geometry of the roadway. <br />
<br />
Maintaining the appropriate amount of pavement friction is critical for safe driving. In locations where drivers may brake excessively, for example, when going around curves, down hills or steep grades, or when approaching an intersection, the road surface can become prematurely polished, reducing the pavement friction and allowing vehicles to skid when the drivers brake. Wet road surfaces can lead to lower friction resulting in skidding or hydroplaning. Refer to the [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/friction.cfm Every Day Counts (EDC) 2012 Initiatives website]. HFST can improve wet crash locations as well as locations that would benefit from increases in friction due to the geometry of the roadway. <br />
<br />
High Friction Surface Treatments place a thin layer of specially engineered, durable, high friction aggregates as a topping on a thermosetting polymer resin binder – usually polymeric, modified polyester, or urethane. These aggregate systems have a long lasting skid resistance and also make the overlay much more resistant to wear and polishing. The resin or polymer binder combination locks the aggregate firmly in place, creating an extremely rough, hard, durable surface capable of withstanding everyday roadway demands such as heavy braking and even snowplowing. HFST restores pavement surface friction characteristics where traffic has worn down existing pavement surface aggregates. HFST can also help compensate for inadequate geometric designs such as sharp curves and/or substandard or variable superelevations. Refer to [http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/pdfs/fhwa-cai-14-019_faqs_hfst_mar2014_508.pdf FHWA's HFST FAQs website]. <br />
<br />
Missouri’s first HFST was placed on US 54 in Jefferson City in the fall of 2013. This location had a history of wet weather crashes. Several low to mid-cost safety improvements were tried, but over time were not able to alleviate all wet weather incidents. This project and three others in the Central District were paid by a [http://www.fhwa.dot.gov/hfl/ Highways for Life] grant. Due to the success of these projects, Missouri applied for and received federal funding to install HFST in every district through the [http://www.fhwa.dot.gov/accelerating/grants/ Accelerating Innovation Deployment (AID)] grant.<br />
<br />
==Placement of HFST==<br />
[[image:HFST.jpg|right|550px]]<br />
<br />
'''Curves'''<br />
<br />
The following table is from [http://d2dtl5nnlpfr0r.cloudfront.net/tti.tamu.edu/documents/TTI-2012-8.pdf ''Using High Friction Surface Treatments to Improve Safety at Horizontal Curves''], a July 2012 Texas A&M Transportation Institute report. It provides guidance on the location to begin placement in advance of the [http://epg.modot.mo.gov/index.php?title=905.1_Traffic_Data_Collection#905.1.2.6_Measuring_Degree_of_Curvature PC] of a curve. The approach speed should be the operating speed as determined by a field analysis, and the curve speed is the posted advisory speed. Engineering judgment and field evaluation should be used to determine the beginning and the length of the treatment. The HFST can often be ended at the [http://epg.modot.mo.gov/index.php?title=905.1_Traffic_Data_Collection#905.1.2.6_Measuring_Degree_of_Curvature PT].<br />
<center><br />
<br />
{| border="1" class="wikitable" style="margin: 1em auto 1em auto" style="text-align:center"<br />
|+'''Recommended Upstream Distance of the PC to Begin HFST Application (ft.)'''<br />
! rowspan="2" style="background:#BEBEBE" width="200"|Approach Speed (mph) !! colspan="7" style="background:#BEBEBE" |Curve Speed (mph)<br />
|-<br />
! style="background:#BEBEBE" width="65"|30 !! style="background:#BEBEBE" width="65"|35 !! style="background:#BEBEBE" width="65"|40 !! style="background:#BEBEBE" width="65"|45 !! style="background:#BEBEBE" width="65"|50 !! style="background:#BEBEBE" width="65"|55 !! style="background:#BEBEBE" width="65"|60 <br />
|-<br />
|35 || 35 || || || || || || <br />
|-<br />
|40 ||76 ||41|| || || || ||<br />
|-<br />
|45 ||122||86||46|| || || ||<br />
|-<br />
|50||173||138||97||51|| || ||<br />
|-<br />
|55||230||194||154||108||57|| ||<br />
|-<br />
|60||292||257||216||170||119||62||<br />
|-<br />
|65||359||324||284||238||186||130||68 <br />
|}<br />
</center><br />
<br />
<br />
'''Intersections'''<br />
<br />
Stopping sight distance can be used to determine the length of the HFST prior to an intersection. However, if frequent back-ups occur, it might be necessary to increase the length of the HFST upstream of the intersection. [http://epg.modot.mo.gov/index.php?title=230.2_Vertical_Alignment#230.2.5_Stopping_Sight_Distance_and_K_Factors EPG 230.2.5 Stopping Sight Distance and K Factors] provides guidance on stopping sight distance.<br />
<br />
'''Grades'''<br />
<br />
[http://epg.modot.mo.gov/files/5/5b/Green_Book_Table_3-36.pdf Table 3-36] (involves grade), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)<br />
<br />
[http://epg.modot.mo.gov/files/b/b7/Green_Book_Table_3-34.pdf Table 3-34] (no grade change), from ''A Policy on Geometric Design of Highways and Streets, 2011'' (the Green Book)</div>Smithk