Stiffness matching of model reinforced concrete for centrifuge modelling of soil-structure interaction

In this paper, three dynamic centrifuge tests were conducted on a pile-reinforced cohe-sionless slope at 1: 50 scale to demonstrate that a recently developed model Reinforced Concrete (RC) pile can model prototype Soil-Structure Interaction (SSI) correctly. Two different pile models were used, namely: (i) model RC piles, representative of 500 mm square precast piles and (ii) 'elastic' piles, fabricated from aluminium-alloy to match the elastic bending stiffness of the model RC piles. Two of the models used RC piles and the third used 'elastic' instrumented piles. In each model, the piles were installed in a row, midway between the toe and crest, at a normalised spacing ratio of 3.5. From the induced bending moments measured in the elastic piles and the measured slope settlements it is shown that elastic soil-pile interaction is replicated accurately by the model RC piles, so long as the induced bending moments are below the moment capacity of the model RC section. It is therefore verified that the elastic behaviour of the model concrete translates to prototype scale.