<p><p><figure id='attachment_3606' style='max-width:6876px' class='caption aligncenter'><img class="wp-image-3606 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Schematic diagram of the generic vibrocompaction process." width="6876" height="4012" /><figcaption class='caption-text'> Generic vibrocompaction process. (Figure courtesy of FHWA, Elias et al. 2006).</figcaption></figure></p><p><h2>Project Summary/Scope:</h2>A new terminal was constructed to serve as a docking and cargo container storage facility. Unsuitable materials were removed through dredging and then backfilled with clean sand. Prefabricated vertical drains were used to accelerate consolidation of underlying clays and vibrocompaction was used to densify the backfill material and reduce liquefaction potential. No dewatering was performed.</p><p>Subsurface Conditions: 27 feet of marsh mud and soft organics required removal through dredging. Clean sands were used as backfill to 10 feet above the water table.</p><p>The project size was approximately 23 acres.<br><h2>Complementary Technologies Used:</h2>Prefabricated Vertical Drains (PVDs)<br><h2>Performance Monitoring<strong>:</strong></h2>PVDs were installed to accelerate consolidation of the underlying clays. Vibrocompaction helped densify the 1.5 million cubic yards of loose sand backfill.<br><h2>Cost Information:</h2>By avoiding dewatering and installation of compacted backfill layers through the use of PVDs and vibrocompaction, considerable cost savings were achieved.<br><h2>Project Technical Paper:</h2>Hussin, J.D. and Foshee, F. (1994). “Wando Terminal Ground Improvement Program.” <em>Proceedings of the Second International Conference on Dredging</em>, Dredging, ’94, ASCE. <a href="http://ascelibrary.org">http://ascelibrary.org</a><h2>Summary Source:<strong> </strong></h2>Elias, V., Welsh, J., Warren, J., Lukas, R., Collin, J.G., and Berg, R.B. (2006). “Ground Improvement Methods-Volume I and II.” Federal Highway Administration, Publication No. FHWA NHI-06-019 (Vol. I) and FHWA NHI-06-020 (Vol. II).<br><h2>Date Case History Prepared:</h2>November 2012</p><p>&nbsp;</p></p>