<p><p><h2>Preferred QC/QA Procedures</h2>The Federal Highway Administration (FHWA) provides QC/QA guidance in the <em>Geosynthetic Design & Construction Guidelines – Reference Manual </em>(FHWA NHI-07-092) which is referenced in the table below.</p><p><table class='tablepress' id='tablepress-1968'><thead><th><center>Publication Title</th><th><center>Publication
Year
</th><th><center>Publication Number</th><th><center>Available for Download</th></thead><tbody><tr><td ><center>Geosynthetic Design & Construction Guidelines – Reference Manual</td><td > <center>2008</td><td > <center>FHWA NHI-07-092</td><td > <center>No<sup>1</td></tr></tbody></table><br><p class="disclaimer"><sup>1</sup> Materials can be ordered through <a href="http://www.nhi.fhwa.dot.gov/">www.nhi.fhwa.dot.gov</a></p>Construction quality is achieved by meeting established requirements, as detailed in project plans and specifications, including applicable codes and standards. Quality Control (QC) and Quality Assurance (QA) are terms applied to the procedures, measurements, and observations used to ensure that construction satisfies the requirements in the project plans and specifications. QC and QA are often misunderstood and used interchangeably. Herein, Quality Control refers to procedures, measurements, and observations used by the contractor to monitor and control the construction quality such that all applicable requirements are satisfied. Quality Assurance refers to measurements and observations by the owner or the owner's engineer to provide assurance to the owner that the facility has been constructed in accordance with the plans and specifications.</p><p>In the FHWA Reference Manual <em>Geosynthetic Design and Construction Guidelines</em>, Holtz et al. (2008) discusses QC/QA requirements throughout the section referencing “Reinforced Embankments on Soft Foundations.” However, a concise listing of the requirements of the QC/QA program is not provided. The components of QC/QA monitoring programs for projects utilizing geosynthetic reinforced embankments are listed in Tables 1, 2, and 3. The entries in the table are a list of typical items, not a list of all methods that could be used for QC/QA. Some QC procedures and measurement items may also serve as QA procedures and measurement items.<br><h3><strong> </strong><strong>TABLE 1. TYPICAL EXISTING QC/QA PROCEDURES AND MEASUREMENT ITEMS</strong></h3><table class='tablepress' id='tablepress-1969'><thead><th><center>QC or QA</th><th><center>Material or Process</th><th><center>Items</th></thead><tbody><tr><td ><center>QC</td><td ><center>Material Related</td><td >•Embankment soil shear strength
•Soil reinforcement tensile seam strength
</td></tr><tr><td ><center>QC</td><td ><center>Process Control</td><td >•Monitor foundation pore water pressure
•Monitor settlement and fill thickness
•Monitor soil reinforcement placement geometries
</td></tr><tr><td ><center>QA</td><td ><center>Material Related</td><td >•Soil shear strength testing
•Soil reinforcement coupon testing
•Soil reinforcement seam coupon testing
•Soil reinforcement manufacturer’s certification
</td></tr><tr><td ><center>QA</td><td ><center>Process Control</td><td >•Monitor foundation pore water pressure
•Monitor thickness of soil lifts
•Monitor settlement and fill thickness
•Monitor soil reinforcement placement geometries
•Monitor soil reinforcement quantities
</td></tr></tbody></table><br><h3><strong>TABLE 2. PERFORMANCE CRITERIA USE IN QC/QA MONITORING PROGRAMS </strong></h3><table class='tablepress' id='tablepress-1970'><thead><th><center>Topics</th><th><center>Items</th></thead><tbody><tr><td ><center>Material Parameters</td><td >•Monitor soil reinforcement strain
•Foundation soil shear strength gain over time
</td></tr><tr><td ><center>System Behavior</td><td >•Embankment settlement
•Foundation pore water pressure
•Lateral deformation response of embankment and foundation soil
</td></tr></tbody></table><br><h3><strong>TABLE 3. EMERGING QC/QA PROCEDURES AND MEASUREMENT ITEMS</strong></h3><table class='tablepress' id='tablepress-1971'><thead><th><center>Topics</th><th><center>Items</th></thead><tbody><tr><td ><center>Material Related</td><td >•None noted</td></tr><tr><td ><center>Process Control</td><td >•Intelligent geosynthetic
•Automated instrumentation
</td></tr></tbody></table></p></p>
<p><p><h2>QC/QA Guidelines</h2>Inspections, construction observations, daily logs, and record keeping are essential QC/QA activities for all technologies. These activities help to ensure and/or verify that:<br><ul> <li>Good construction practices and the project specifications are followed.</li> <li>Problems can be anticipated before they occur, in some cases.</li> <li>Problems that do arise are caught early, and their cause can oftentimes be identified.</li> <li>All parties are in good communication.</li> <li>The project is on schedule.</li></ul>Additional technology-specific details for inspections, construction observations, daily logs, and record keeping QC/QA activities are provided in the <em>Individual QC/QA Methods </em>section below.<strong> </strong></p></p>
<p><p><h2>References</h2>Holtz, R.D., Christopher, B.R., and Berg, R.R. (2008). <em>Geosynthetic Design and Construction Guidelines</em>, U.S. DOT, Federal Highway Administration, Washington, DC, FHWA-HI-07-092, 460p.</p><p>Paylor, M.R., Christopher, B.R., and Nyren, R.R. (2008). “Intelligent geosynthetics used for performance monitoring and construction control: Woodrow Wilson bridge – Maryland portion,” <em>The First Pan American Geosynthetics Conference & Exhibition,</em> Cancun, Mexico, 744-753.</p><p> </p></p>