Centrifugal test and numerical assessment for settlement of a large-scale artificial island constructed on deep marine clays

Abstract

This paper presents a testing and numerical study on the deformation behaviours of marine clays from Jinzhou Bay, China, where a large-scale artificial island is under construction for the Dalian offshore airport. The mechanical behaviours of marine clays were investigated by laboratory tests, triaxial creep tests and centrifugal test. An elasto-viscoplastic constitutive model (Adachi-Oka model) and a finite element programme (CFEM 2D) were used to calculate the deformation of the marine clays. The validation of the elasto-viscoplastic model and finite element programme was initially verified by the numerical simulation of triaxial creep test and the centrifugal test. In addition, the settlement of the large-scale artificial island was calculated by the verified programme, which accounted for the effect of non-linear hydraulic conductivity. The calculated results show that differential settlement exists between functional areas, with the greatest post-construction settlement attaining 288 cm in 100 years. Uneven distribution of excess pore water pressure also exists, and does not fully dissipate in 100 years. It can be concluded that the settlement of the artificial island will continue, hence enough attention should be paid.