<p><p><h2>Commentary</h2>Payment for jet grouting typically consists of a grouting pay item measured by the cubic yard (CY).

<p><p><figure id='attachment_2603' style='max-width:780px' class='caption aligncenter'><img class="wp-image-2603 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Schematic of the principle of jet grouting operations." width="780" height="481" /><figcaption class='caption-text'> Principle of Jet Grouting Operation (After Kutzner, C.

<p><p><strong>Reference(s):<br></strong><em>Ho (2007)</em></p><p>This procedure is highly theoretical and rarely, if ever, used in practice. The procedure presents a way to determine the jet penetration distance using a model that is based on jet hydrodynamics and soil mechanics.

<p><p><strong>References:<br></strong><em>Burke et al. (2000a, 2000b)</em></p><p><strong>Method Summary</strong></p><p>A survey of each column should be performed to ensure the columns are in the correct location. This is usually done by conventional surveying methods.

<p><p><strong>References:<br></strong><em>Bruce (2007a)<br>Bruce et al. (2001)<br>Burke et al. (2000a, 2000b)<br>Gularte et al. (2007)<br>Maswoswe (2003)</em></p><p><strong>Method Summary</strong></p><p>The jetting parameters should be monitored and recorded continuously throughout the grouting operation.

<p><p><strong>References:<br></strong><em>Bruce et al. (2001)</em></p><p><strong>Method Summary</strong></p><p>Seismic surveys can be used to determine whether there has been an overall improvement in the soil mass. This is typically done by cross-hole tomography.

<p><p><strong>References:<br></strong><em>Bruce et al. (2001)<br>Burke et al. (2000a)<br>Kauschinger et al. (1992)</em></p><p><strong>Method Summary</strong></p><p>Samples should be taken from the spoils regularly and tested for cement content. Cement content can be determined based on the heat produced when the soil-cement sample is neutralized with a buffering solution consisting of sodium acetate and glacial acetic acid.

<p><p><strong>References:<br></strong><em>Schorr et al. (2007)</em></p><p><strong>Method Summary</strong></p><p>Vibrations produced by the jet are measured as a column is formed next to a completed column. These vibrations are analyzed, and the difference in vibrations between the native soil and the grouted soil in the neighboring column is determined.

<p><p><strong>References:<br></strong><em>Bruce et al. (2001)<br>Burke et al. (2007a)<br>Maswoswe (2003)<br>Meyers et al. (2004)<br>Nicholson and Bruce (1996)</em></p><p><strong>Method Summary</strong></p><p>Wet-grab samples are samples of the soilcrete taken before it has cured. The samples should be taken almost immediately after completion of the column, and samples should be taken from several different depths in the same column.