... of the caisson walls on Port Island where there was a vertical seismic array.1 A typical example of the forward movement of a caisson wall is shown in Fig. 1. 1.07 m LWL 0.0 m 2.8 m Caisson fill Stone backfill Fig. 1. Sketch of outward movement of caisson wall at Port Island, Kobe 1 SEA Backfill soil Replaced...

... have been restored by various methods. Collapse settlement 8. Collapsesettlementoccursoninundation of a body of fillby ground or surface water. In the case of opencast backfill this can occur at depthoncessation of any pumpingoperations, or close to ground level as surface water penetrates...