Use in geotextile-encased granular columns

For cases in which the available construction time is limited or serviceabiUty criteria are high, methods other than basal-reinforced embankments need to be chosen. Most commonly, ground improvement using stone or gravel columns is chosen. However if the foundation soil is extremely soft, the use of conventional stone columns can lead to unacceptable deformation or even failure. This is because the soft soil 

The arrangement of GECs produces a ductile bearing system that is immune to buckling under the incident column loads. The use of GECs considerably reduces both absolute and differential settlement and enhances structural stabUity both during construction and after completion (Fig. 16.3). 

Since the concentration of stress over the column heads produces a reduction in the loads acting on the soft stratum between the columns, creep settlement (from the consolidation of soft soil between the columns) is much lower when encased columns are used compared with an unimproved subsoil. This reduction in creep settlement as 

0 Geotextile encased granular column 0 Soft soil Rrm bearing layer 

2 Vertical stability analysis of geotextile-encased columns 

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