Assessment of Superposition as a Design Framework for the Combined Effects of Soil Improvement and Foundation Remediation

Abstract

The problem of pile foundation reuse provides an ideal opportunity to evaluate the validity of superposition as a design paradigm for ground intervention and ground reinforcement (GIGR) techniques when used in combination with in situ foundations. Grouted, helical piers, a relatively new technology, are proposed as a capacity improvement option for existing pile foundations. The relationship between these geotechnical elements was evaluated through the axial and lateral testing of small-scale, cast-in-place foundations in uniform, dry sand. These tests showed that the implementation of ground modification techniques caused an increase in the axial and lateral load-deflection performance of the foundation, with superposition as the most probable design methodology.