River North Residential Development Lot 7 - Stone Column Densification Portland, Oregon Back to Project List   Vibratory Ground Improvement Wet Top Feed Stone Columns were installed to provide foundation support of a residential housing development adjacent to the Willamette River. Project Overview: Foundation support and mitigation of liquefaction potential of the underlying loose saturated soils for the river front project were important structural design considerations for the residential development. Vibratory ground improvement was chosen to address these structural design issues. Stone columns were installed using crushed gravel to densify the loose sandy soils for support of the residential structures. Verification testing by the Engineer indicated that the liquefaction potential at the site had been reduced to withstand the design earthquake.   Value of Work Performed: $552,400 Project Duration: 3 months Project Completion Date: February 2006