Evaluation of Soft Boundary Effects (SBE) on the Behaviour of a Shallow Foundation

The increase in complexity of geotechnical problems demand for more advanced physical modelling and instrumentation approaches. However, the limitations in the space, especially for the centrifuge modelling, and hence the boundary effects are often present in such experiments. This paper shortly reviews the common quantification methods of hard mechanical boundary effects, and describes the recent experiments using softer boundaries as a compensation measure. The main part of the paper however focuses on the evaluation of the effects of soft lateral boundaries on the pre- and post-peak load-displacement responses of a shallow foundation. Advanced image analysis techniques are used to monitor the evolution of strains at the hard and softer lateral borders and relate these observations to the mechanical behaviour of the foundation.