Soil improvement techniques are commonly used to mitigate one of the major and most complex problems that can occur during and after a seismic event – liquefaction triggering of soil deposits. Following several research programs and efforts of the scientific community to find methods to mitigate the liquefaction hazard, stone columns and jet grout columns were found to be the most common solutions used to decrease the likelihood and severity of foundation movements caused by earthquake-induced soil liquefaction and lateral spreading. The stone column method relies on additional drainage and the densification of the soil around the column, resulting in the reduction of pore water pressures and shear stress levels during seismic excitation. The jet grout columns, when forming cells (lattice structure), contain the soil during the seismic demand; this greatly reduces the shear stresses in the soil, with the consequent reduction on the liquefaction potential of the treated soil block.
Subjects: None provided
Author: Antonio Cristovao, David Brito and Abilio Nogueira
Publisher: DFI, EFFC