Study on the Design Settlement of Over-Consolidated Clay for a Complex Development

Abstract

The purpose of this study was to understand the consolidation settlement characteristics of the west coast, where overconsolidation has occurred, and to identify the problems of existing consolidation design through field tests and the re-evaluation of design parameters. The settlement ratio (measurement settlement/design settlement) obtained using the existing design method was calculated to be 56.0%; however, the settlement ratio obtained through the re-evaluation of the preconsolidation stress and compression index suggested in this study was 95.6-96.6%. It was applicable to the west coast region, where the condition of overconsolidation developed. In addition, the consolidation test curve of the low-plasticity silt ground in the west coast region showed a rounded curve with no clear inflection point. It was difficult to determine the preconsolidation stress when applying the Casagrande method, and it tended to be underestimated. Analysis showed that it is preferable to apply the compression index obtained from the compaction curve as it is, rather than to apply Schmertmann's modified compression index.