<p><p><strong>References:<br></strong><em>Forssblad (1980)</em></p><p><strong>Method Summary</strong></p><p>Ground elevation change or settlement is monitored through GPS measurements from the roller for each roller pass, which is a measure of compaction. Elevations can also be monitored by independent measurements using string lines and tape measure or by using advanced methods including GPS, robotic total station, and laser levels. The test method involves performing compaction passes until no significant decrease in ground elevation is observed. This method provides a simple and yet effective means to assess compaction. Forssblad (1980) showed good correlations between ground settlement and CCC measurements. This method can be used both for QC and QA.</p><p><em> </em><strong>Accuracy and Precision</strong></p><p>The accuracy and precision of the method depends on the test method used. Laser levels and robotic total station measurements are considered very accurate and precise. String line and tape measures are relatively less accurate.</p><p><strong>Adequacy of Coverage</strong></p><p>The coverage adequacy depends on the number of measurement points. If roller mounted GPS is used, it provides almost near continuous data. GPS or laser receivers can be mounted on a truck to collect continuous data.</p><p><strong> </strong><strong>Implementation Requirements </strong></p><p>These tests are relatively easy and rapid to perform compared to most other QC/QA tests. Use of GPS, robotic total station, and laser levels may require specialized equipment and training. Use of these methods on soils compacted using padfoot rollers may have difficulties due to irregular surfaces.</p><p><strong><em> </em></strong><strong>General Comments </strong></p><p>This test method can be effectively used for QC.</p></p>