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The influence of lateral pre-stressing on shear strength and stiffness of soils

Researcher(s)

Principal investigators:

Project status

Completed

Start date: 01/01/03
End date: 12/01/03

Sponsor(s)/partner(s)

Sponsor(s): Geopier Foundation Company

About the research

Abstract: This research describes an experimental study to investigate the influence of the lateral pre-stressing archieved from the installation of pressure-injected footings on the behavior of the Iowa loess. The investigation was carried out based on four series of stress path control tests in which soil specimens were consolidated under induced lateral stress before being vertically sheared in both drained and undrained conditions. The lateral stress appeared to be more effective than the vertical stress in terms of desifying the soil during consolidation. The yielding and the critical state of the soil were found to be dependent on the drainage condition following the lateral consolidation process and the pre-shearing mean consolidation effective stress.

It was observed that shear strength, vertical stiffness, and preconsolidation vertical effective stress of the soil could be siginificantly increased after being laterally consolidated even the mean consolidation stress did not exceed the original preconsolidation value. The findings in this research led to a hypothesis that consolidation of soils under induced lateral stress may alter the soil fabric thus creating a totally new material as compared with the original soil.