Investigating the Creep Behaviour of Marine Soft Structured Clay by FEM with an Elasto-viscoplastic Constitutive Model.

Abstract

The time-dependent creep deformation of marine soft-structured clay is a major cause of foundation failure on soft grounds around the globe. This study focuses on the analysis of the drained and undrained time-dependent creep behavior of a normally consolidated (NC)-Kyuhoji marine soft-structured clay by FEM with a new Elasto-viscoplastic (EVP) constitutive model. One-dimensional creep and consolidated undrained creep element tests are simulated to analyze the creep behavior of soft clay under constant load conditions. The creep period of 1157days is used in the drained state with consolidation pressures from 100 kPa to 450 kPa with 50 kPa incremental intervals. The undrained time-dependent creep behavior of Kyuhoji clay is analyzed under varying constant creep stresses-qcrp (0.3qf, 0.5qf, 0.6qf, and 0.7qf, where qf is the undrained peak strength), and creep periods (11.6days, 463 days, and 5787days). The results show the capability of the new EVP model in analyzing creep failure behavior of marine soft-structured clayey and can explain the reason for the premature abrupt collapse of foundations on soil grounds where drainage is impeded under constant load.

Abstract

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