<p><p><strong>References:<br></strong><em>Elias et al. (2006)<br>Hussin (2001)<br>Serridge and Synac (2007)</em></p><p><strong>Method Summary</strong></p><p>VCCs are similar to other structural elements in that the design of the element is only valid if the materials used in construction have the strengths assumed during design. Verification of the material properties is essential. The case history discussed in the FHWA (Elias et al.

<p><p><strong>References:<br></strong><em>Schaefer et al. (2016)<br>Elias et al. (2006)<br>Hussin (1994)<br>Schaefer et al. (1997)<br>Serridge and Synac (2007)</em></p><p><strong>Method Summary</strong></p><p>The installation of each VCC should be monitored during the construction process to ensure that the columns are installed with proper geometry.

Reference(s):
Hussin (1994)
Hussin et al. (2001)
Mankbadi et al. (2004)
Mankbadi et al. (2008)
Schaefer et al. (1997)
Serridge and Synac (2007)
Zamiskie et al. (2004)

<p><p><strong>References:<br></strong><em>Serridge and Synac (2007)</em></p><p><strong>Method Summary</strong></p><p>The integrity of the installed columns can be checked for depth or defects. Sonic integrity testing is a non-destructive testing method that consists of sending a low-strain wave through the column and measuring the time it takes for the wave to reflect back to the top of the column.

<p><p><strong>References:<br></strong><em>Schaefer et al. (2016).<br>Hussin (1994)<br>ISSMGE TC-17 Working Group D, Report D4<br>Mankbadi et al. (2004)<br>Mankbadi et al. (2008)<br>Schaefer et al. (1997)<br>Serridge and Synac (2007)</em></p><p><strong>Method Summary</strong></p><p>There is a limited availability of verified design methods used to predict the soil-column interaction parameters and settlement characteristics of VCCs.

<p><p><figure id='attachment_3612' style='max-width:372px' class='caption aligncenter'><img class="wp-image-3612 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Schematic of site conditions." width="372" height="357" /><figcaption class='caption-text'> Schematic of site conditions.

<p><p><h2>Commentary</h2>The costs of Vibro-Concrete Columns (VCCs) on a highway project are typically captured in a contract bid item which is measured by the lineal foot (LF). Included in this bid item are the material, equipment, labor, and incidentals to construct a VCC.

<p><p><figure id='attachment_2639' style='max-width:475px' class='caption aligncenter'><img class="wp-image-2639 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Diagram of vibro concrete column installation. " width="475" height="630" /><figcaption class='caption-text'> Diagram of vibro concrete column installation.