Lateral behaviour of a pile group due to side-by-side twin tunnelling in dry sand: 3D centrifuge tests and numerical modelling

This paper presents lateral responses of an existing 2 × 2 pile group to advancement of side-by-side twin tunnels (with 1% volume loss) at various depths in dry sand using 3D centrifuge and numerical modelling. The tunnels were located near mid-depth of the pile shaft (test SS), next to (test TT) and below the toe (test BB) of the pile group. The largest and the smallest lateral movement of the pile cap was induced after first tunnelling in test TT and test SS, respectively. The shearing force was induced in piles as a reaction of pile deflection in tests TT and BB.