Modelling creep of soft Finnish clay

Abstract

This project was done in the Laboratory of Soil Mechanics and foundation engineering at the Helsinki University of Technology (HUT).

The aim of this project was to study the simulation of settlement in the long term i.e. to understand the creep behavior of clay. Indeed the secondary consolidation is a major concern when buildings, roads, embankments and other structures are founded on deep clay layers. This settlement causes high costs of maintenance in the life span of a structure.

To proceed tests have been carried out in the laboratory and data of former long duration oedometer tests have been gathered. These data have then been processed and analysed in order to extract the right parameters defining the different clays. Once these parameters obtained simulations with PLAXIS’ “Soft Soil Creep model” and also classical modelling have been performed. The simulated and observed results have then been compared enabling us to start the reflection about the acquisition of the parameters to model the long term behavior. Attempt to improve this data process, to stick more accurately to the actual behavior, have also been carried out.