ABSTRACT
The present paper is focused on the Impact Rammed Aggregate Pier system, a ground improvement technology developed by Geopier Foundation Company. From extensive in-situ tests also including blast tests, Impact elements have proven to be very effective at densifying in-situ granular soils and increasing the factor of safety against liquefaction. The intent of the paper is to verify the methods that are used to evaluate liquefaction mitigation with Impact piers. One method to evaluate the mitigation of liquefaction risk for design of Impact piers is to estimate the increase in CPT tip resistance qc expected after installation of the Impact elements. In the paper we will consider CPTu tests performed before and after Impact installations in various sites worldwide to attempt to verify the accuracy of formulas from literature and to try to understand which aspects can be refined in future studies. The future aim is to possibly modify the formulas to account for local soil conditions in the Emilia-Romagna region in Italy.
